path: root/contrib/tools/cython/Cython/Compiler/Parsing.py

# cython: auto_cpdef=True, infer_types=True, language_level=3, py2_import=True 
# 
#   Parser 
# 
 
from __future__ import absolute_import 
 
# This should be done automatically 
import cython 
cython.declare(Nodes=object, ExprNodes=object, EncodedString=object, 
               bytes_literal=object, StringEncoding=object,
               FileSourceDescriptor=object, lookup_unicodechar=object, unicode_category=object,
               Future=object, Options=object, error=object, warning=object, 
               Builtin=object, ModuleNode=object, Utils=object, _unicode=object, _bytes=object,
               re=object, sys=object, _parse_escape_sequences=object, _parse_escape_sequences_raw=object,
               partial=object, reduce=object, _IS_PY3=cython.bint, _IS_2BYTE_UNICODE=cython.bint,
               _CDEF_MODIFIERS=tuple)
 
from io import StringIO
import re 
import sys
from unicodedata import lookup as lookup_unicodechar, category as unicode_category
from functools import partial, reduce
 
from .Scanning import PyrexScanner, FileSourceDescriptor, StringSourceDescriptor
from . import Nodes 
from . import ExprNodes 
from . import Builtin 
from . import StringEncoding 
from .StringEncoding import EncodedString, bytes_literal, _unicode, _bytes
from .ModuleNode import ModuleNode 
from .Errors import error, warning 
from .. import Utils 
from . import Future 
from . import Options 
 
_IS_PY3 = sys.version_info[0] >= 3
_IS_2BYTE_UNICODE = sys.maxunicode == 0xffff
_CDEF_MODIFIERS = ('inline', 'nogil', 'api')
 

class Ctx(object): 
    #  Parsing context 
    level = 'other' 
    visibility = 'private' 
    cdef_flag = 0 
    typedef_flag = 0 
    api = 0 
    overridable = 0 
    nogil = 0 
    namespace = None 
    templates = None 
    allow_struct_enum_decorator = False 
 
    def __init__(self, **kwds): 
        self.__dict__.update(kwds) 
 
    def __call__(self, **kwds): 
        ctx = Ctx() 
        d = ctx.__dict__ 
        d.update(self.__dict__) 
        d.update(kwds) 
        return ctx 
 

def p_ident(s, message="Expected an identifier"):
    if s.sy == 'IDENT': 
        name = s.systring 
        s.next() 
        return name 
    else: 
        s.error(message) 
 
def p_ident_list(s): 
    names = [] 
    while s.sy == 'IDENT': 
        names.append(s.systring) 
        s.next() 
        if s.sy != ',': 
            break 
        s.next() 
    return names 
 
#------------------------------------------ 
# 
#   Expressions 
# 
#------------------------------------------ 
 
def p_binop_operator(s): 
    pos = s.position() 
    op = s.sy 
    s.next() 
    return op, pos 
 
def p_binop_expr(s, ops, p_sub_expr): 
    n1 = p_sub_expr(s) 
    while s.sy in ops: 
        op, pos = p_binop_operator(s) 
        n2 = p_sub_expr(s) 
        n1 = ExprNodes.binop_node(pos, op, n1, n2) 
        if op == '/': 
            if Future.division in s.context.future_directives: 
                n1.truedivision = True 
            else: 
                n1.truedivision = None # unknown 
    return n1 
 
#lambdef: 'lambda' [varargslist] ':' test 
 
def p_lambdef(s, allow_conditional=True): 
    # s.sy == 'lambda' 
    pos = s.position() 
    s.next() 
    if s.sy == ':': 
        args = [] 
        star_arg = starstar_arg = None 
    else: 
        args, star_arg, starstar_arg = p_varargslist( 
            s, terminator=':', annotated=False) 
    s.expect(':') 
    if allow_conditional: 
        expr = p_test(s) 
    else: 
        expr = p_test_nocond(s) 
    return ExprNodes.LambdaNode( 
        pos, args = args, 
        star_arg = star_arg, starstar_arg = starstar_arg, 
        result_expr = expr) 
 
#lambdef_nocond: 'lambda' [varargslist] ':' test_nocond 
 
def p_lambdef_nocond(s): 
    return p_lambdef(s, allow_conditional=False) 
 
#test: or_test ['if' or_test 'else' test] | lambdef 
 
def p_test(s): 
    if s.sy == 'lambda': 
        return p_lambdef(s) 
    pos = s.position() 
    expr = p_or_test(s) 
    if s.sy == 'if': 
        s.next() 
        test = p_or_test(s) 
        s.expect('else') 
        other = p_test(s) 
        return ExprNodes.CondExprNode(pos, test=test, true_val=expr, false_val=other) 
    else: 
        return expr 
 
#test_nocond: or_test | lambdef_nocond 
 
def p_test_nocond(s): 
    if s.sy == 'lambda': 
        return p_lambdef_nocond(s) 
    else: 
        return p_or_test(s) 
 
#or_test: and_test ('or' and_test)* 
 
def p_or_test(s): 
    return p_rassoc_binop_expr(s, ('or',), p_and_test) 
 
def p_rassoc_binop_expr(s, ops, p_subexpr): 
    n1 = p_subexpr(s) 
    if s.sy in ops: 
        pos = s.position() 
        op = s.sy 
        s.next() 
        n2 = p_rassoc_binop_expr(s, ops, p_subexpr) 
        n1 = ExprNodes.binop_node(pos, op, n1, n2) 
    return n1 
 
#and_test: not_test ('and' not_test)* 
 
def p_and_test(s): 
    #return p_binop_expr(s, ('and',), p_not_test) 
    return p_rassoc_binop_expr(s, ('and',), p_not_test) 
 
#not_test: 'not' not_test | comparison 
 
def p_not_test(s): 
    if s.sy == 'not': 
        pos = s.position() 
        s.next() 
        return ExprNodes.NotNode(pos, operand = p_not_test(s)) 
    else: 
        return p_comparison(s) 
 
#comparison: expr (comp_op expr)* 
#comp_op: '<'|'>'|'=='|'>='|'<='|'<>'|'!='|'in'|'not' 'in'|'is'|'is' 'not' 
 
def p_comparison(s): 
    n1 = p_starred_expr(s) 
    if s.sy in comparison_ops: 
        pos = s.position() 
        op = p_cmp_op(s) 
        n2 = p_starred_expr(s) 
        n1 = ExprNodes.PrimaryCmpNode(pos, 
            operator = op, operand1 = n1, operand2 = n2) 
        if s.sy in comparison_ops: 
            n1.cascade = p_cascaded_cmp(s) 
    return n1 
 
def p_test_or_starred_expr(s): 
    if s.sy == '*': 
        return p_starred_expr(s) 
    else: 
        return p_test(s) 
 
def p_starred_expr(s): 
    pos = s.position() 
    if s.sy == '*': 
        starred = True 
        s.next() 
    else: 
        starred = False 
    expr = p_bit_expr(s) 
    if starred: 
        expr = ExprNodes.StarredUnpackingNode(pos, expr)
    return expr 
 
def p_cascaded_cmp(s): 
    pos = s.position() 
    op = p_cmp_op(s) 
    n2 = p_starred_expr(s) 
    result = ExprNodes.CascadedCmpNode(pos, 
        operator = op, operand2 = n2) 
    if s.sy in comparison_ops: 
        result.cascade = p_cascaded_cmp(s) 
    return result 
 
def p_cmp_op(s): 
    if s.sy == 'not': 
        s.next() 
        s.expect('in') 
        op = 'not_in' 
    elif s.sy == 'is': 
        s.next() 
        if s.sy == 'not': 
            s.next() 
            op = 'is_not' 
        else: 
            op = 'is' 
    else: 
        op = s.sy 
        s.next() 
    if op == '<>': 
        op = '!=' 
    return op 
 
comparison_ops = cython.declare(set, set([ 
    '<', '>', '==', '>=', '<=', '<>', '!=', 
    'in', 'is', 'not' 
])) 
 
#expr: xor_expr ('|' xor_expr)* 
 
def p_bit_expr(s): 
    return p_binop_expr(s, ('|',), p_xor_expr) 
 
#xor_expr: and_expr ('^' and_expr)* 
 
def p_xor_expr(s): 
    return p_binop_expr(s, ('^',), p_and_expr) 
 
#and_expr: shift_expr ('&' shift_expr)* 
 
def p_and_expr(s): 
    return p_binop_expr(s, ('&',), p_shift_expr) 
 
#shift_expr: arith_expr (('<<'|'>>') arith_expr)* 
 
def p_shift_expr(s): 
    return p_binop_expr(s, ('<<', '>>'), p_arith_expr) 
 
#arith_expr: term (('+'|'-') term)* 
 
def p_arith_expr(s): 
    return p_binop_expr(s, ('+', '-'), p_term) 
 
#term: factor (('*'|'@'|'/'|'%'|'//') factor)* 
 
def p_term(s): 
    return p_binop_expr(s, ('*', '@', '/', '%', '//'), p_factor) 
 
#factor: ('+'|'-'|'~'|'&'|typecast|sizeof) factor | power 
 
def p_factor(s): 
    # little indirection for C-ification purposes 
    return _p_factor(s) 
 
def _p_factor(s): 
    sy = s.sy 
    if sy in ('+', '-', '~'): 
        op = s.sy 
        pos = s.position() 
        s.next() 
        return ExprNodes.unop_node(pos, op, p_factor(s)) 
    elif not s.in_python_file: 
        if sy == '&': 
            pos = s.position() 
            s.next() 
            arg = p_factor(s) 
            return ExprNodes.AmpersandNode(pos, operand = arg) 
        elif sy == "<": 
            return p_typecast(s) 
        elif sy == 'IDENT' and s.systring == "sizeof": 
            return p_sizeof(s) 
    return p_power(s) 
 
def p_typecast(s): 
    # s.sy == "<" 
    pos = s.position() 
    s.next() 
    base_type = p_c_base_type(s) 
    is_memslice = isinstance(base_type, Nodes.MemoryViewSliceTypeNode) 
    is_template = isinstance(base_type, Nodes.TemplatedTypeNode) 
    is_const = isinstance(base_type, Nodes.CConstTypeNode) 
    if (not is_memslice and not is_template and not is_const 
        and base_type.name is None): 
        s.error("Unknown type") 
    declarator = p_c_declarator(s, empty = 1) 
    if s.sy == '?': 
        s.next() 
        typecheck = 1 
    else: 
        typecheck = 0 
    s.expect(">") 
    operand = p_factor(s) 
    if is_memslice: 
        return ExprNodes.CythonArrayNode(pos, base_type_node=base_type, 
                                         operand=operand) 
 
    return ExprNodes.TypecastNode(pos, 
        base_type = base_type, 
        declarator = declarator, 
        operand = operand, 
        typecheck = typecheck) 
 
def p_sizeof(s): 
    # s.sy == ident "sizeof" 
    pos = s.position() 
    s.next() 
    s.expect('(') 
    # Here we decide if we are looking at an expression or type 
    # If it is actually a type, but parsable as an expression, 
    # we treat it as an expression here. 
    if looking_at_expr(s): 
        operand = p_test(s) 
        node = ExprNodes.SizeofVarNode(pos, operand = operand) 
    else: 
        base_type = p_c_base_type(s) 
        declarator = p_c_declarator(s, empty = 1) 
        node = ExprNodes.SizeofTypeNode(pos, 
            base_type = base_type, declarator = declarator) 
    s.expect(')') 
    return node 
 

def p_yield_expression(s): 
    # s.sy == "yield" 
    pos = s.position() 
    s.next() 
    is_yield_from = False 
    if s.sy == 'from': 
        is_yield_from = True 
        s.next() 
    if s.sy != ')' and s.sy not in statement_terminators: 
        # "yield from" does not support implicit tuples, but "yield" does ("yield 1,2")
        arg = p_test(s) if is_yield_from else p_testlist(s)
    else: 
        if is_yield_from: 
            s.error("'yield from' requires a source argument", 
                    pos=pos, fatal=False) 
        arg = None 
    if is_yield_from: 
        return ExprNodes.YieldFromExprNode(pos, arg=arg) 
    else: 
        return ExprNodes.YieldExprNode(pos, arg=arg) 
 

def p_yield_statement(s): 
    # s.sy == "yield" 
    yield_expr = p_yield_expression(s) 
    return Nodes.ExprStatNode(yield_expr.pos, expr=yield_expr) 
 
 
def p_async_statement(s, ctx, decorators):
    # s.sy >> 'async' ...
    if s.sy == 'def':
        # 'async def' statements aren't allowed in pxd files
        if 'pxd' in ctx.level:
            s.error('def statement not allowed here')
        s.level = ctx.level
        return p_def_statement(s, decorators, is_async_def=True)
    elif decorators:
        s.error("Decorators can only be followed by functions or classes")
    elif s.sy == 'for':
        return p_for_statement(s, is_async=True)
    elif s.sy == 'with':
        s.next()
        return p_with_items(s, is_async=True)
    else:
        s.error("expected one of 'def', 'for', 'with' after 'async'")


#power: atom_expr ('**' factor)*
#atom_expr: ['await'] atom trailer*

def p_power(s): 
    if s.systring == 'new' and s.peek()[0] == 'IDENT': 
        return p_new_expr(s) 
    await_pos = None
    if s.sy == 'await':
        await_pos = s.position()
        s.next()
    n1 = p_atom(s) 
    while s.sy in ('(', '[', '.'): 
        n1 = p_trailer(s, n1) 
    if await_pos:
        n1 = ExprNodes.AwaitExprNode(await_pos, arg=n1)
    if s.sy == '**': 
        pos = s.position() 
        s.next() 
        n2 = p_factor(s) 
        n1 = ExprNodes.binop_node(pos, '**', n1, n2) 
    return n1 
 

def p_new_expr(s): 
    # s.systring == 'new'. 
    pos = s.position() 
    s.next() 
    cppclass = p_c_base_type(s) 
    return p_call(s, ExprNodes.NewExprNode(pos, cppclass = cppclass)) 
 
#trailer: '(' [arglist] ')' | '[' subscriptlist ']' | '.' NAME 
 
def p_trailer(s, node1): 
    pos = s.position() 
    if s.sy == '(': 
        return p_call(s, node1) 
    elif s.sy == '[': 
        return p_index(s, node1) 
    else: # s.sy == '.' 
        s.next() 
        name = p_ident(s)
        return ExprNodes.AttributeNode(pos, 
            obj=node1, attribute=name)
 

# arglist:  argument (',' argument)* [','] 
# argument: [test '='] test       # Really [keyword '='] test 
 
# since PEP 448:
# argument: ( test [comp_for] |
#             test '=' test |
#             '**' expr |
#             star_expr )

def p_call_parse_args(s, allow_genexp=True):
    # s.sy == '(' 
    pos = s.position() 
    s.next() 
    positional_args = [] 
    keyword_args = [] 
    starstar_seen = False
    last_was_tuple_unpack = False
    while s.sy != ')':
        if s.sy == '*': 
            if starstar_seen:
                s.error("Non-keyword arg following keyword arg", pos=s.position())
            s.next() 
            positional_args.append(p_test(s))
            last_was_tuple_unpack = True
        elif s.sy == '**':
            s.next()
            keyword_args.append(p_test(s))
            starstar_seen = True
        else: 
            arg = p_test(s) 
            if s.sy == '=': 
                s.next() 
                if not arg.is_name: 
                    s.error("Expected an identifier before '='", 
                            pos=arg.pos) 
                encoded_name = s.context.intern_ustring(arg.name)
                keyword = ExprNodes.IdentifierStringNode( 
                    arg.pos, value=encoded_name) 
                arg = p_test(s) 
                keyword_args.append((keyword, arg)) 
            else: 
                if keyword_args: 
                    s.error("Non-keyword arg following keyword arg", pos=arg.pos)
                if positional_args and not last_was_tuple_unpack:
                    positional_args[-1].append(arg)
                else:
                    positional_args.append([arg])
                last_was_tuple_unpack = False
        if s.sy != ',': 
            break 
        s.next() 
 
    if s.sy in ('for', 'async'):
        if not keyword_args and not last_was_tuple_unpack:
            if len(positional_args) == 1 and len(positional_args[0]) == 1:
                positional_args = [[p_genexp(s, positional_args[0][0])]]
    s.expect(')') 
    return positional_args or [[]], keyword_args
 

def p_call_build_packed_args(pos, positional_args, keyword_args):
    keyword_dict = None 

    subtuples = [
        ExprNodes.TupleNode(pos, args=arg) if isinstance(arg, list) else ExprNodes.AsTupleNode(pos, arg=arg)
        for arg in positional_args
    ]
    # TODO: implement a faster way to join tuples than creating each one and adding them
    arg_tuple = reduce(partial(ExprNodes.binop_node, pos, '+'), subtuples)

    if keyword_args:
        kwargs = []
        dict_items = []
        for item in keyword_args:
            if isinstance(item, tuple):
                key, value = item
                dict_items.append(ExprNodes.DictItemNode(pos=key.pos, key=key, value=value))
            elif item.is_dict_literal:
                # unpack "**{a:b}" directly
                dict_items.extend(item.key_value_pairs)
            else:
                if dict_items:
                    kwargs.append(ExprNodes.DictNode(
                        dict_items[0].pos, key_value_pairs=dict_items, reject_duplicates=True))
                    dict_items = []
                kwargs.append(item)

        if dict_items:
            kwargs.append(ExprNodes.DictNode(
                dict_items[0].pos, key_value_pairs=dict_items, reject_duplicates=True))

        if kwargs:
            if len(kwargs) == 1 and kwargs[0].is_dict_literal:
                # only simple keyword arguments found -> one dict
                keyword_dict = kwargs[0]
            else:
                # at least one **kwargs
                keyword_dict = ExprNodes.MergedDictNode(pos, keyword_args=kwargs)

    return arg_tuple, keyword_dict 
 

def p_call(s, function): 
    # s.sy == '(' 
    pos = s.position() 
    positional_args, keyword_args = p_call_parse_args(s)
 
    if not keyword_args and len(positional_args) == 1 and isinstance(positional_args[0], list):
        return ExprNodes.SimpleCallNode(pos, function=function, args=positional_args[0])
    else: 
        arg_tuple, keyword_dict = p_call_build_packed_args(pos, positional_args, keyword_args)
        return ExprNodes.GeneralCallNode(
            pos, function=function, positional_args=arg_tuple, keyword_args=keyword_dict)
 

#lambdef: 'lambda' [varargslist] ':' test 
 
#subscriptlist: subscript (',' subscript)* [','] 
 
def p_index(s, base): 
    # s.sy == '[' 
    pos = s.position() 
    s.next() 
    subscripts, is_single_value = p_subscript_list(s) 
    if is_single_value and len(subscripts[0]) == 2: 
        start, stop = subscripts[0] 
        result = ExprNodes.SliceIndexNode(pos, 
            base = base, start = start, stop = stop) 
    else: 
        indexes = make_slice_nodes(pos, subscripts) 
        if is_single_value: 
            index = indexes[0] 
        else: 
            index = ExprNodes.TupleNode(pos, args = indexes) 
        result = ExprNodes.IndexNode(pos, 
            base = base, index = index) 
    s.expect(']') 
    return result 
 
def p_subscript_list(s): 
    is_single_value = True 
    items = [p_subscript(s)] 
    while s.sy == ',': 
        is_single_value = False 
        s.next() 
        if s.sy == ']': 
            break 
        items.append(p_subscript(s)) 
    return items, is_single_value 
 
#subscript: '.' '.' '.' | test | [test] ':' [test] [':' [test]] 
 
def p_subscript(s): 
    # Parse a subscript and return a list of 
    # 1, 2 or 3 ExprNodes, depending on how 
    # many slice elements were encountered. 
    pos = s.position() 
    start = p_slice_element(s, (':',)) 
    if s.sy != ':': 
        return [start] 
    s.next() 
    stop = p_slice_element(s, (':', ',', ']')) 
    if s.sy != ':': 
        return [start, stop] 
    s.next() 
    step = p_slice_element(s, (':', ',', ']')) 
    return [start, stop, step] 
 
def p_slice_element(s, follow_set): 
    # Simple expression which may be missing iff 
    # it is followed by something in follow_set. 
    if s.sy not in follow_set: 
        return p_test(s) 
    else: 
        return None 
 
def expect_ellipsis(s): 
    s.expect('.') 
    s.expect('.') 
    s.expect('.') 
 
def make_slice_nodes(pos, subscripts): 
    # Convert a list of subscripts as returned 
    # by p_subscript_list into a list of ExprNodes, 
    # creating SliceNodes for elements with 2 or 
    # more components. 
    result = [] 
    for subscript in subscripts: 
        if len(subscript) == 1: 
            result.append(subscript[0]) 
        else: 
            result.append(make_slice_node(pos, *subscript)) 
    return result 
 
def make_slice_node(pos, start, stop = None, step = None): 
    if not start: 
        start = ExprNodes.NoneNode(pos) 
    if not stop: 
        stop = ExprNodes.NoneNode(pos) 
    if not step: 
        step = ExprNodes.NoneNode(pos) 
    return ExprNodes.SliceNode(pos, 
        start = start, stop = stop, step = step) 
 
#atom: '(' [yield_expr|testlist_comp] ')' | '[' [listmaker] ']' | '{' [dict_or_set_maker] '}' | '`' testlist '`' | NAME | NUMBER | STRING+ 
 
def p_atom(s): 
    pos = s.position() 
    sy = s.sy 
    if sy == '(': 
        s.next() 
        if s.sy == ')': 
            result = ExprNodes.TupleNode(pos, args = []) 
        elif s.sy == 'yield': 
            result = p_yield_expression(s) 
        else: 
            result = p_testlist_comp(s) 
        s.expect(')') 
        return result 
    elif sy == '[': 
        return p_list_maker(s) 
    elif sy == '{': 
        return p_dict_or_set_maker(s) 
    elif sy == '`': 
        return p_backquote_expr(s) 
    elif sy == '.': 
        expect_ellipsis(s) 
        return ExprNodes.EllipsisNode(pos) 
    elif sy == 'INT': 
        return p_int_literal(s) 
    elif sy == 'FLOAT': 
        value = s.systring 
        s.next() 
        return ExprNodes.FloatNode(pos, value = value) 
    elif sy == 'IMAG': 
        value = s.systring[:-1] 
        s.next() 
        return ExprNodes.ImagNode(pos, value = value) 
    elif sy == 'BEGIN_STRING': 
        kind, bytes_value, unicode_value = p_cat_string_literal(s) 
        if kind == 'c': 
            return ExprNodes.CharNode(pos, value = bytes_value) 
        elif kind == 'u': 
            return ExprNodes.UnicodeNode(pos, value = unicode_value, bytes_value = bytes_value) 
        elif kind == 'b': 
            return ExprNodes.BytesNode(pos, value = bytes_value) 
        elif kind == 'f':
            return ExprNodes.JoinedStrNode(pos, values = unicode_value)
        elif kind == '':
            return ExprNodes.StringNode(pos, value = bytes_value, unicode_value = unicode_value)
        else: 
            s.error("invalid string kind '%s'" % kind)
    elif sy == 'IDENT': 
        name = s.systring
        if name == "None": 
            result = ExprNodes.NoneNode(pos)
        elif name == "True": 
            result = ExprNodes.BoolNode(pos, value=True)
        elif name == "False": 
            result = ExprNodes.BoolNode(pos, value=False)
        elif name == "NULL" and not s.in_python_file: 
            result = ExprNodes.NullNode(pos)
        else: 
            result = p_name(s, name)
        s.next()
        return result
    else: 
        s.error("Expected an identifier or literal") 
 
def p_int_literal(s): 
    pos = s.position() 
    value = s.systring 
    s.next() 
    unsigned = "" 
    longness = "" 
    while value[-1] in u"UuLl": 
        if value[-1] in u"Ll": 
            longness += "L" 
        else: 
            unsigned += "U" 
        value = value[:-1] 
    # '3L' is ambiguous in Py2 but not in Py3.  '3U' and '3LL' are 
    # illegal in Py2 Python files.  All suffixes are illegal in Py3 
    # Python files. 
    is_c_literal = None 
    if unsigned: 
        is_c_literal = True 
    elif longness: 
        if longness == 'LL' or s.context.language_level >= 3: 
            is_c_literal = True 
    if s.in_python_file: 
        if is_c_literal: 
            error(pos, "illegal integer literal syntax in Python source file") 
        is_c_literal = False 
    return ExprNodes.IntNode(pos, 
                             is_c_literal = is_c_literal, 
                             value = value, 
                             unsigned = unsigned, 
                             longness = longness) 
 
 
def p_name(s, name): 
    pos = s.position() 
    if not s.compile_time_expr and name in s.compile_time_env: 
        value = s.compile_time_env.lookup_here(name) 
        node = wrap_compile_time_constant(pos, value) 
        if node is not None: 
            return node 
    return ExprNodes.NameNode(pos, name=name) 
 
 
def wrap_compile_time_constant(pos, value): 
    rep = repr(value) 
    if value is None: 
        return ExprNodes.NoneNode(pos) 
    elif value is Ellipsis: 
        return ExprNodes.EllipsisNode(pos) 
    elif isinstance(value, bool): 
        return ExprNodes.BoolNode(pos, value=value) 
    elif isinstance(value, int): 
        return ExprNodes.IntNode(pos, value=rep, constant_result=value)
    elif isinstance(value, float): 
        return ExprNodes.FloatNode(pos, value=rep, constant_result=value)
    elif isinstance(value, complex):
        node = ExprNodes.ImagNode(pos, value=repr(value.imag), constant_result=complex(0.0, value.imag))
        if value.real:
            # FIXME: should we care about -0.0 ?
            # probably not worth using the '-' operator for negative imag values
            node = ExprNodes.binop_node(
                pos, '+', ExprNodes.FloatNode(pos, value=repr(value.real), constant_result=value.real), node,
                constant_result=value)
        return node
    elif isinstance(value, _unicode): 
        return ExprNodes.UnicodeNode(pos, value=EncodedString(value)) 
    elif isinstance(value, _bytes): 
        bvalue = bytes_literal(value, 'ascii')  # actually: unknown encoding, but BytesLiteral requires one
        return ExprNodes.BytesNode(pos, value=bvalue, constant_result=value)
    elif isinstance(value, tuple): 
        args = [wrap_compile_time_constant(pos, arg) 
                for arg in value] 
        if None not in args: 
            return ExprNodes.TupleNode(pos, args=args) 
        else: 
            # error already reported 
            return None 
    elif not _IS_PY3 and isinstance(value, long):
        return ExprNodes.IntNode(pos, value=rep.rstrip('L'), constant_result=value)
    error(pos, "Invalid type for compile-time constant: %r (type %s)" 
               % (value, value.__class__.__name__)) 
    return None 
 
 
def p_cat_string_literal(s): 
    # A sequence of one or more adjacent string literals. 
    # Returns (kind, bytes_value, unicode_value) 
    # where kind in ('b', 'c', 'u', 'f', '')
    pos = s.position()
    kind, bytes_value, unicode_value = p_string_literal(s) 
    if kind == 'c' or s.sy != 'BEGIN_STRING': 
        return kind, bytes_value, unicode_value 
    bstrings, ustrings, positions = [bytes_value], [unicode_value], [pos]
    bytes_value = unicode_value = None 
    while s.sy == 'BEGIN_STRING': 
        pos = s.position() 
        next_kind, next_bytes_value, next_unicode_value = p_string_literal(s) 
        if next_kind == 'c': 
            error(pos, "Cannot concatenate char literal with another string or char literal") 
            continue
        elif next_kind != kind: 
            # concatenating f strings and normal strings is allowed and leads to an f string
            if set([kind, next_kind]) in (set(['f', 'u']), set(['f', ''])):
                kind = 'f'
            else:
                error(pos, "Cannot mix string literals of different types, expected %s'', got %s''" % (
                    kind, next_kind))
                continue
        bstrings.append(next_bytes_value)
        ustrings.append(next_unicode_value)
        positions.append(pos)
    # join and rewrap the partial literals 
    if kind in ('b', 'c', '') or kind == 'u' and None not in bstrings: 
        # Py3 enforced unicode literals are parsed as bytes/unicode combination 
        bytes_value = bytes_literal(StringEncoding.join_bytes(bstrings), s.source_encoding)
    if kind in ('u', ''): 
        unicode_value = EncodedString(u''.join([u for u in ustrings if u is not None]))
    if kind == 'f':
        unicode_value = []
        for u, pos in zip(ustrings, positions):
            if isinstance(u, list):
                unicode_value += u
            else:
                # non-f-string concatenated into the f-string
                unicode_value.append(ExprNodes.UnicodeNode(pos, value=EncodedString(u)))
    return kind, bytes_value, unicode_value 
 

def p_opt_string_literal(s, required_type='u'): 
    if s.sy != 'BEGIN_STRING':
        return None
    pos = s.position()
    kind, bytes_value, unicode_value = p_string_literal(s, required_type)
    if required_type == 'u':
        if kind == 'f':
            s.error("f-string not allowed here", pos)
        return unicode_value
    elif required_type == 'b':
        return bytes_value
    else: 
        s.error("internal parser configuration error")
 

def check_for_non_ascii_characters(string): 
    for c in string: 
        if c >= u'\x80': 
            return True 
    return False 
 

def p_string_literal(s, kind_override=None): 
    # A single string or char literal.  Returns (kind, bvalue, uvalue) 
    # where kind in ('b', 'c', 'u', 'f', '').  The 'bvalue' is the source
    # code byte sequence of the string literal, 'uvalue' is the 
    # decoded Unicode string.  Either of the two may be None depending 
    # on the 'kind' of string, only unprefixed strings have both 
    # representations. In f-strings, the uvalue is a list of the Unicode
    # strings and f-string expressions that make up the f-string.
 
    # s.sy == 'BEGIN_STRING' 
    pos = s.position() 
    is_python3_source = s.context.language_level >= 3 
    has_non_ascii_literal_characters = False
    string_start_pos = (pos[0], pos[1], pos[2] + len(s.systring))
    kind_string = s.systring.rstrip('"\'').lower()
    if len(kind_string) > 1:
        if len(set(kind_string)) != len(kind_string):
            error(pos, 'Duplicate string prefix character')
        if 'b' in kind_string and 'u' in kind_string:
            error(pos, 'String prefixes b and u cannot be combined')
        if 'b' in kind_string and 'f' in kind_string:
            error(pos, 'String prefixes b and f cannot be combined')
        if 'u' in kind_string and 'f' in kind_string:
            error(pos, 'String prefixes u and f cannot be combined')

    is_raw = 'r' in kind_string

    if 'c' in kind_string:
        # this should never happen, since the lexer does not allow combining c
        # with other prefix characters
        if len(kind_string) != 1:
            error(pos, 'Invalid string prefix for character literal')
        kind = 'c'
    elif 'f' in kind_string:
        kind = 'f'     # u is ignored
        is_raw = True  # postpone the escape resolution
    elif 'b' in kind_string:
        kind = 'b'
    elif 'u' in kind_string:
        kind = 'u'
    else:
        kind = '' 

    if kind == '' and kind_override is None and Future.unicode_literals in s.context.future_directives: 
        chars = StringEncoding.StrLiteralBuilder(s.source_encoding) 
        kind = 'u' 
    else: 
        if kind_override is not None and kind_override in 'ub': 
            kind = kind_override 
        if kind in ('u', 'f'):  # f-strings are scanned exactly like Unicode literals, but are parsed further later
            chars = StringEncoding.UnicodeLiteralBuilder() 
        elif kind == '': 
            chars = StringEncoding.StrLiteralBuilder(s.source_encoding) 
        else: 
            chars = StringEncoding.BytesLiteralBuilder(s.source_encoding) 
 
    while 1: 
        s.next() 
        sy = s.sy 
        systr = s.systring 
        # print "p_string_literal: sy =", sy, repr(s.systring) ###
        if sy == 'CHARS': 
            chars.append(systr) 
            if is_python3_source and not has_non_ascii_literal_characters and check_for_non_ascii_characters(systr):
                has_non_ascii_literal_characters = True
        elif sy == 'ESCAPE': 
            # in Py2, 'ur' raw unicode strings resolve unicode escapes but nothing else
            if is_raw and (is_python3_source or kind != 'u' or systr[1] not in u'Uu'):
                chars.append(systr) 
                if is_python3_source and not has_non_ascii_literal_characters and check_for_non_ascii_characters(systr):
                    has_non_ascii_literal_characters = True
            else: 
                _append_escape_sequence(kind, chars, systr, s)
        elif sy == 'NEWLINE': 
            chars.append(u'\n') 
        elif sy == 'END_STRING': 
            break 
        elif sy == 'EOF': 
            s.error("Unclosed string literal", pos=pos) 
        else: 
            s.error("Unexpected token %r:%r in string literal" % (
                sy, s.systring))
 
    if kind == 'c': 
        unicode_value = None 
        bytes_value = chars.getchar() 
        if len(bytes_value) != 1: 
            error(pos, u"invalid character literal: %r" % bytes_value) 
    else: 
        bytes_value, unicode_value = chars.getstrings() 
        if (has_non_ascii_literal_characters
                and is_python3_source and Future.unicode_literals in s.context.future_directives):
            # Python 3 forbids literal non-ASCII characters in byte strings 
            if kind == 'b':
                s.error("bytes can only contain ASCII literal characters.", pos=pos)
            bytes_value = None 
    if kind == 'f':
        unicode_value = p_f_string(s, unicode_value, string_start_pos, is_raw='r' in kind_string)
    s.next() 
    return (kind, bytes_value, unicode_value) 
 

def _append_escape_sequence(kind, builder, escape_sequence, s):
    c = escape_sequence[1]
    if c in u"01234567":
        builder.append_charval(int(escape_sequence[1:], 8))
    elif c in u"'\"\\":
        builder.append(c)
    elif c in u"abfnrtv":
        builder.append(StringEncoding.char_from_escape_sequence(escape_sequence))
    elif c == u'\n':
        pass  # line continuation
    elif c == u'x':  # \xXX
        if len(escape_sequence) == 4:
            builder.append_charval(int(escape_sequence[2:], 16))
        else:
            s.error("Invalid hex escape '%s'" % escape_sequence, fatal=False)
    elif c in u'NUu' and kind in ('u', 'f', ''):  # \uxxxx, \Uxxxxxxxx, \N{...}
        chrval = -1
        if c == u'N':
            uchar = None
            try:
                uchar = lookup_unicodechar(escape_sequence[3:-1])
                chrval = ord(uchar)
            except KeyError:
                s.error("Unknown Unicode character name %s" %
                        repr(escape_sequence[3:-1]).lstrip('u'), fatal=False)
            except TypeError:
                # 2-byte unicode build of CPython?
                if (uchar is not None and _IS_2BYTE_UNICODE and len(uchar) == 2 and
                        unicode_category(uchar[0]) == 'Cs' and unicode_category(uchar[1]) == 'Cs'):
                    # surrogate pair instead of single character
                    chrval = 0x10000 + (ord(uchar[0]) - 0xd800) >> 10 + (ord(uchar[1]) - 0xdc00)
                else:
                    raise
        elif len(escape_sequence) in (6, 10):
            chrval = int(escape_sequence[2:], 16)
            if chrval > 1114111:  # sys.maxunicode:
                s.error("Invalid unicode escape '%s'" % escape_sequence)
                chrval = -1
        else:
            s.error("Invalid unicode escape '%s'" % escape_sequence, fatal=False)
        if chrval >= 0:
            builder.append_uescape(chrval, escape_sequence)
    else:
        builder.append(escape_sequence)


_parse_escape_sequences_raw, _parse_escape_sequences = [re.compile((
    # escape sequences:
    br'(\\(?:' +
    (br'\\?' if is_raw else (
        br'[\\abfnrtv"\'{]|'
        br'[0-7]{2,3}|'
        br'N\{[^}]*\}|'
        br'x[0-9a-fA-F]{2}|'
        br'u[0-9a-fA-F]{4}|'
        br'U[0-9a-fA-F]{8}|'
        br'[NxuU]|'  # detect invalid escape sequences that do not match above
    )) +
    br')?|'
    # non-escape sequences:
    br'\{\{?|'
    br'\}\}?|'
    br'[^\\{}]+)'
    ).decode('us-ascii')).match
    for is_raw in (True, False)]


def _f_string_error_pos(pos, string, i):
    return (pos[0], pos[1], pos[2] + i + 1)  # FIXME: handle newlines in string


def p_f_string(s, unicode_value, pos, is_raw):
    # Parses a PEP 498 f-string literal into a list of nodes. Nodes are either UnicodeNodes
    # or FormattedValueNodes.
    values = []
    next_start = 0
    size = len(unicode_value)
    builder = StringEncoding.UnicodeLiteralBuilder()
    _parse_seq = _parse_escape_sequences_raw if is_raw else _parse_escape_sequences

    while next_start < size:
        end = next_start
        match = _parse_seq(unicode_value, next_start)
        if match is None:
            error(_f_string_error_pos(pos, unicode_value, next_start), "Invalid escape sequence")

        next_start = match.end()
        part = match.group()
        c = part[0]
        if c == '\\':
            if not is_raw and len(part) > 1:
                _append_escape_sequence('f', builder, part, s)
            else:
                builder.append(part)
        elif c == '{':
            if part == '{{':
                builder.append('{')
            else:
                # start of an expression
                if builder.chars:
                    values.append(ExprNodes.UnicodeNode(pos, value=builder.getstring()))
                    builder = StringEncoding.UnicodeLiteralBuilder()
                next_start, expr_node = p_f_string_expr(s, unicode_value, pos, next_start, is_raw)
                values.append(expr_node)
        elif c == '}':
            if part == '}}':
                builder.append('}')
            else:
                error(_f_string_error_pos(pos, unicode_value, end),
                      "f-string: single '}' is not allowed")
        else:
            builder.append(part)

    if builder.chars:
        values.append(ExprNodes.UnicodeNode(pos, value=builder.getstring()))
    return values


def p_f_string_expr(s, unicode_value, pos, starting_index, is_raw):
    # Parses a {}-delimited expression inside an f-string. Returns a FormattedValueNode
    # and the index in the string that follows the expression.
    i = starting_index
    size = len(unicode_value)
    conversion_char = terminal_char = format_spec = None
    format_spec_str = None
    NO_CHAR = 2**30

    nested_depth = 0
    quote_char = NO_CHAR
    in_triple_quotes = False
    backslash_reported = False

    while True:
        if i >= size:
            break  # error will be reported below
        c = unicode_value[i]

        if quote_char != NO_CHAR:
            if c == '\\':
                # avoid redundant error reports along '\' sequences
                if not backslash_reported:
                    error(_f_string_error_pos(pos, unicode_value, i),
                          "backslashes not allowed in f-strings")
                backslash_reported = True
            elif c == quote_char:
                if in_triple_quotes:
                    if i + 2 < size and unicode_value[i + 1] == c and unicode_value[i + 2] == c:
                        in_triple_quotes = False
                        quote_char = NO_CHAR
                        i += 2
                else:
                    quote_char = NO_CHAR
        elif c in '\'"':
            quote_char = c
            if i + 2 < size and unicode_value[i + 1] == c and unicode_value[i + 2] == c:
                in_triple_quotes = True
                i += 2
        elif c in '{[(':
            nested_depth += 1
        elif nested_depth != 0 and c in '}])':
            nested_depth -= 1
        elif c == '#':
            error(_f_string_error_pos(pos, unicode_value, i),
                  "format string cannot include #")
        elif nested_depth == 0 and c in '!:}':
            # allow != as a special case
            if c == '!' and i + 1 < size and unicode_value[i + 1] == '=':
                i += 1
                continue

            terminal_char = c
            break
        i += 1

    # normalise line endings as the parser expects that
    expr_str = unicode_value[starting_index:i].replace('\r\n', '\n').replace('\r', '\n')
    expr_pos = (pos[0], pos[1], pos[2] + starting_index + 2)  # TODO: find exact code position (concat, multi-line, ...)

    if not expr_str.strip():
        error(_f_string_error_pos(pos, unicode_value, starting_index),
              "empty expression not allowed in f-string")

    if terminal_char == '!':
        i += 1
        if i + 2 > size:
            pass  # error will be reported below
        else:
            conversion_char = unicode_value[i]
            i += 1
            terminal_char = unicode_value[i]

    if terminal_char == ':':
        in_triple_quotes = False
        in_string = False
        nested_depth = 0
        start_format_spec = i + 1
        while True:
            if i >= size:
                break  # error will be reported below
            c = unicode_value[i]
            if not in_triple_quotes and not in_string:
                if c == '{':
                    nested_depth += 1
                elif c == '}':
                    if nested_depth > 0:
                        nested_depth -= 1
                    else:
                        terminal_char = c
                        break
            if c in '\'"':
                if not in_string and i + 2 < size and unicode_value[i + 1] == c and unicode_value[i + 2] == c:
                    in_triple_quotes = not in_triple_quotes
                    i += 2
                elif not in_triple_quotes:
                    in_string = not in_string
            i += 1

        format_spec_str = unicode_value[start_format_spec:i]

    if terminal_char != '}':
        error(_f_string_error_pos(pos, unicode_value, i),
              "missing '}' in format string expression" + (
                  ", found '%s'" % terminal_char if terminal_char else ""))

    # parse the expression as if it was surrounded by parentheses
    buf = StringIO('(%s)' % expr_str)
    scanner = PyrexScanner(buf, expr_pos[0], parent_scanner=s, source_encoding=s.source_encoding, initial_pos=expr_pos)
    expr = p_testlist(scanner)  # TODO is testlist right here?

    # validate the conversion char
    if conversion_char is not None and not ExprNodes.FormattedValueNode.find_conversion_func(conversion_char):
        error(expr_pos, "invalid conversion character '%s'" % conversion_char)

    # the format spec is itself treated like an f-string
    if format_spec_str:
        format_spec = ExprNodes.JoinedStrNode(pos, values=p_f_string(s, format_spec_str, pos, is_raw))

    return i + 1, ExprNodes.FormattedValueNode(
        pos, value=expr, conversion_char=conversion_char, format_spec=format_spec)


# since PEP 448:
# list_display  ::=     "[" [listmaker] "]"
# listmaker     ::=     (test|star_expr) ( comp_for | (',' (test|star_expr))* [','] )
# comp_iter     ::=     comp_for | comp_if 
# comp_for      ::=     ["async"] "for" expression_list "in" testlist [comp_iter]
# comp_if       ::=     "if" test [comp_iter]
 
def p_list_maker(s): 
    # s.sy == '[' 
    pos = s.position() 
    s.next() 
    if s.sy == ']': 
        s.expect(']') 
        return ExprNodes.ListNode(pos, args=[])

    expr = p_test_or_starred_expr(s)
    if s.sy in ('for', 'async'):
        if expr.is_starred:
            s.error("iterable unpacking cannot be used in comprehension")
        append = ExprNodes.ComprehensionAppendNode(pos, expr=expr) 
        loop = p_comp_for(s, append) 
        s.expect(']') 
        return ExprNodes.ComprehensionNode( 
            pos, loop=loop, append=append, type=Builtin.list_type,
            # list comprehensions leak their loop variable in Py2 
            has_local_scope=s.context.language_level >= 3)

    # (merged) list literal
    if s.sy == ',':
        s.next()
        exprs = p_test_or_starred_expr_list(s, expr)
    else: 
        exprs = [expr]
    s.expect(']')
    return ExprNodes.ListNode(pos, args=exprs)
 

def p_comp_iter(s, body): 
    if s.sy in ('for', 'async'):
        return p_comp_for(s, body) 
    elif s.sy == 'if': 
        return p_comp_if(s, body) 
    else: 
        # insert the 'append' operation into the loop 
        return body 
 
def p_comp_for(s, body): 
    pos = s.position()
    # [async] for ...
    is_async = False
    if s.sy == 'async':
        is_async = True
        s.next()

    # s.sy == 'for' 
    s.expect('for')
    kw = p_for_bounds(s, allow_testlist=False, is_async=is_async)
    kw.update(else_clause=None, body=p_comp_iter(s, body), is_async=is_async)
    return Nodes.ForStatNode(pos, **kw) 
 
def p_comp_if(s, body): 
    # s.sy == 'if' 
    pos = s.position() 
    s.next() 
    test = p_test_nocond(s) 
    return Nodes.IfStatNode(pos, 
        if_clauses = [Nodes.IfClauseNode(pos, condition = test, 
                                         body = p_comp_iter(s, body))], 
        else_clause = None ) 
 
 
# since PEP 448:
#dictorsetmaker: ( ((test ':' test | '**' expr)
#                   (comp_for | (',' (test ':' test | '**' expr))* [','])) |
#                  ((test | star_expr)
#                   (comp_for | (',' (test | star_expr))* [','])) )

def p_dict_or_set_maker(s): 
    # s.sy == '{' 
    pos = s.position() 
    s.next() 
    if s.sy == '}': 
        s.next() 
        return ExprNodes.DictNode(pos, key_value_pairs=[])

    parts = []
    target_type = 0
    last_was_simple_item = False
    while True:
        if s.sy in ('*', '**'):
            # merged set/dict literal
            if target_type == 0:
                target_type = 1 if s.sy == '*' else 2  # 'stars'
            elif target_type != len(s.sy):
                s.error("unexpected %sitem found in %s literal" % (
                    s.sy, 'set' if target_type == 1 else 'dict'))
            s.next() 
            if s.sy == '*':
                s.error("expected expression, found '*'")
            item = p_starred_expr(s)
            parts.append(item)
            last_was_simple_item = False
        else:
            item = p_test(s)
            if target_type == 0:
                target_type = 2 if s.sy == ':' else 1  # dict vs. set
            if target_type == 2:
                # dict literal
                s.expect(':')
                key = item
                value = p_test(s)
                item = ExprNodes.DictItemNode(key.pos, key=key, value=value)
            if last_was_simple_item:
                parts[-1].append(item)
            else:
                parts.append([item])
                last_was_simple_item = True

        if s.sy == ',':
            s.next()
            if s.sy == '}': 
                break 
        else:
            break

    if s.sy in ('for', 'async'):
        # dict/set comprehension
        if len(parts) == 1 and isinstance(parts[0], list) and len(parts[0]) == 1:
            item = parts[0][0]
            if target_type == 2:
                assert isinstance(item, ExprNodes.DictItemNode), type(item)
                comprehension_type = Builtin.dict_type
                append = ExprNodes.DictComprehensionAppendNode(
                    item.pos, key_expr=item.key, value_expr=item.value)
            else:
                comprehension_type = Builtin.set_type
                append = ExprNodes.ComprehensionAppendNode(item.pos, expr=item)
            loop = p_comp_for(s, append) 
            s.expect('}') 
            return ExprNodes.ComprehensionNode(pos, loop=loop, append=append, type=comprehension_type)
        else: 
            # syntax error, try to find a good error message
            if len(parts) == 1 and not isinstance(parts[0], list):
                s.error("iterable unpacking cannot be used in comprehension")
            else:
                # e.g. "{1,2,3 for ..."
                s.expect('}')
            return ExprNodes.DictNode(pos, key_value_pairs=[])

    s.expect('}')
    if target_type == 1:
        # (merged) set literal
        items = []
        set_items = []
        for part in parts:
            if isinstance(part, list):
                set_items.extend(part)
            else:
                if set_items:
                    items.append(ExprNodes.SetNode(set_items[0].pos, args=set_items))
                    set_items = []
                items.append(part)
        if set_items:
            items.append(ExprNodes.SetNode(set_items[0].pos, args=set_items))
        if len(items) == 1 and items[0].is_set_literal:
            return items[0]
        return ExprNodes.MergedSequenceNode(pos, args=items, type=Builtin.set_type)
    else: 
        # (merged) dict literal
        items = []
        dict_items = []
        for part in parts:
            if isinstance(part, list):
                dict_items.extend(part)
            else:
                if dict_items:
                    items.append(ExprNodes.DictNode(dict_items[0].pos, key_value_pairs=dict_items))
                    dict_items = []
                items.append(part)
        if dict_items:
            items.append(ExprNodes.DictNode(dict_items[0].pos, key_value_pairs=dict_items))
        if len(items) == 1 and items[0].is_dict_literal:
            return items[0]
        return ExprNodes.MergedDictNode(pos, keyword_args=items, reject_duplicates=False)
 

# NOTE: no longer in Py3 :) 
def p_backquote_expr(s): 
    # s.sy == '`' 
    pos = s.position() 
    s.next() 
    args = [p_test(s)] 
    while s.sy == ',': 
        s.next() 
        args.append(p_test(s)) 
    s.expect('`') 
    if len(args) == 1: 
        arg = args[0] 
    else: 
        arg = ExprNodes.TupleNode(pos, args = args) 
    return ExprNodes.BackquoteNode(pos, arg = arg) 
 
def p_simple_expr_list(s, expr=None): 
    exprs = expr is not None and [expr] or [] 
    while s.sy not in expr_terminators: 
        exprs.append( p_test(s) ) 
        if s.sy != ',': 
            break 
        s.next() 
    return exprs 
 

def p_test_or_starred_expr_list(s, expr=None): 
    exprs = expr is not None and [expr] or [] 
    while s.sy not in expr_terminators: 
        exprs.append(p_test_or_starred_expr(s))
        if s.sy != ',': 
            break 
        s.next() 
    return exprs 
 
 
#testlist: test (',' test)* [','] 
 
def p_testlist(s): 
    pos = s.position() 
    expr = p_test(s) 
    if s.sy == ',': 
        s.next() 
        exprs = p_simple_expr_list(s, expr) 
        return ExprNodes.TupleNode(pos, args = exprs) 
    else: 
        return expr 
 
# testlist_star_expr: (test|star_expr) ( comp_for | (',' (test|star_expr))* [','] ) 
 
def p_testlist_star_expr(s): 
    pos = s.position() 
    expr = p_test_or_starred_expr(s) 
    if s.sy == ',': 
        s.next() 
        exprs = p_test_or_starred_expr_list(s, expr) 
        return ExprNodes.TupleNode(pos, args = exprs) 
    else: 
        return expr 
 
# testlist_comp: (test|star_expr) ( comp_for | (',' (test|star_expr))* [','] ) 
 
def p_testlist_comp(s): 
    pos = s.position() 
    expr = p_test_or_starred_expr(s) 
    if s.sy == ',': 
        s.next() 
        exprs = p_test_or_starred_expr_list(s, expr) 
        return ExprNodes.TupleNode(pos, args = exprs) 
    elif s.sy in ('for', 'async'):
        return p_genexp(s, expr) 
    else: 
        return expr 
 
def p_genexp(s, expr): 
    # s.sy == 'async' | 'for'
    loop = p_comp_for(s, Nodes.ExprStatNode( 
        expr.pos, expr = ExprNodes.YieldExprNode(expr.pos, arg=expr))) 
    return ExprNodes.GeneratorExpressionNode(expr.pos, loop=loop) 
 
expr_terminators = cython.declare(set, set([ 
    ')', ']', '}', ':', '=', 'NEWLINE'])) 
 

#------------------------------------------------------- 
# 
#   Statements 
# 
#------------------------------------------------------- 
 
def p_global_statement(s): 
    # assume s.sy == 'global' 
    pos = s.position() 
    s.next() 
    names = p_ident_list(s) 
    return Nodes.GlobalNode(pos, names = names) 
 

def p_nonlocal_statement(s): 
    pos = s.position() 
    s.next() 
    names = p_ident_list(s) 
    return Nodes.NonlocalNode(pos, names = names) 
 

def p_expression_or_assignment(s): 
    expr = p_testlist_star_expr(s)
    if s.sy == ':' and (expr.is_name or expr.is_subscript or expr.is_attribute):
        s.next()
        expr.annotation = p_test(s)
    if s.sy == '=' and expr.is_starred:
        # This is a common enough error to make when learning Cython to let 
        # it fail as early as possible and give a very clear error message. 
        s.error("a starred assignment target must be in a list or tuple" 
                " - maybe you meant to use an index assignment: var[0] = ...", 
                pos=expr.pos)
    expr_list = [expr]
    while s.sy == '=': 
        s.next() 
        if s.sy == 'yield': 
            expr = p_yield_expression(s) 
        else: 
            expr = p_testlist_star_expr(s) 
        expr_list.append(expr) 
    if len(expr_list) == 1: 
        if re.match(r"([-+*/%^&|]|<<|>>|\*\*|//|@)=", s.sy):
            lhs = expr_list[0] 
            if isinstance(lhs, ExprNodes.SliceIndexNode): 
                # implementation requires IndexNode 
                lhs = ExprNodes.IndexNode( 
                    lhs.pos, 
                    base=lhs.base, 
                    index=make_slice_node(lhs.pos, lhs.start, lhs.stop)) 
            elif not isinstance(lhs, (ExprNodes.AttributeNode, ExprNodes.IndexNode, ExprNodes.NameNode)):
                error(lhs.pos, "Illegal operand for inplace operation.") 
            operator = s.sy[:-1] 
            s.next() 
            if s.sy == 'yield': 
                rhs = p_yield_expression(s) 
            else: 
                rhs = p_testlist(s) 
            return Nodes.InPlaceAssignmentNode(lhs.pos, operator=operator, lhs=lhs, rhs=rhs)
        expr = expr_list[0] 
        return Nodes.ExprStatNode(expr.pos, expr=expr) 
 
    rhs = expr_list[-1] 
    if len(expr_list) == 2: 
        return Nodes.SingleAssignmentNode(rhs.pos, lhs=expr_list[0], rhs=rhs)
    else: 
        return Nodes.CascadedAssignmentNode(rhs.pos, lhs_list=expr_list[:-1], rhs=rhs)
 

def p_print_statement(s): 
    # s.sy == 'print' 
    pos = s.position() 
    ends_with_comma = 0 
    s.next() 
    if s.sy == '>>': 
        s.next() 
        stream = p_test(s) 
        if s.sy == ',': 
            s.next() 
            ends_with_comma = s.sy in ('NEWLINE', 'EOF') 
    else: 
        stream = None 
    args = [] 
    if s.sy not in ('NEWLINE', 'EOF'): 
        args.append(p_test(s)) 
        while s.sy == ',': 
            s.next() 
            if s.sy in ('NEWLINE', 'EOF'): 
                ends_with_comma = 1 
                break 
            args.append(p_test(s)) 
    arg_tuple = ExprNodes.TupleNode(pos, args=args)
    return Nodes.PrintStatNode(pos, 
        arg_tuple=arg_tuple, stream=stream,
        append_newline=not ends_with_comma)
 

def p_exec_statement(s): 
    # s.sy == 'exec' 
    pos = s.position() 
    s.next() 
    code = p_bit_expr(s) 
    if isinstance(code, ExprNodes.TupleNode): 
        # Py3 compatibility syntax 
        tuple_variant = True 
        args = code.args 
        if len(args) not in (2, 3): 
            s.error("expected tuple of length 2 or 3, got length %d" % len(args), 
                    pos=pos, fatal=False) 
            args = [code] 
    else: 
        tuple_variant = False 
        args = [code] 
    if s.sy == 'in': 
        if tuple_variant: 
            s.error("tuple variant of exec does not support additional 'in' arguments", 
                    fatal=False) 
        s.next() 
        args.append(p_test(s)) 
        if s.sy == ',': 
            s.next() 
            args.append(p_test(s)) 
    return Nodes.ExecStatNode(pos, args=args) 
 
def p_del_statement(s): 
    # s.sy == 'del' 
    pos = s.position() 
    s.next() 
    # FIXME: 'exprlist' in Python 
    args = p_simple_expr_list(s) 
    return Nodes.DelStatNode(pos, args = args) 
 
def p_pass_statement(s, with_newline = 0): 
    pos = s.position() 
    s.expect('pass') 
    if with_newline: 
        s.expect_newline("Expected a newline", ignore_semicolon=True) 
    return Nodes.PassStatNode(pos) 
 
def p_break_statement(s): 
    # s.sy == 'break' 
    pos = s.position() 
    s.next() 
    return Nodes.BreakStatNode(pos) 
 
def p_continue_statement(s): 
    # s.sy == 'continue' 
    pos = s.position() 
    s.next() 
    return Nodes.ContinueStatNode(pos) 
 
def p_return_statement(s): 
    # s.sy == 'return' 
    pos = s.position() 
    s.next() 
    if s.sy not in statement_terminators: 
        value = p_testlist(s) 
    else: 
        value = None 
    return Nodes.ReturnStatNode(pos, value = value) 
 
def p_raise_statement(s): 
    # s.sy == 'raise' 
    pos = s.position() 
    s.next() 
    exc_type = None 
    exc_value = None 
    exc_tb = None 
    cause = None 
    if s.sy not in statement_terminators: 
        exc_type = p_test(s) 
        if s.sy == ',': 
            s.next() 
            exc_value = p_test(s) 
            if s.sy == ',': 
                s.next() 
                exc_tb = p_test(s) 
        elif s.sy == 'from': 
            s.next() 
            cause = p_test(s) 
    if exc_type or exc_value or exc_tb: 
        return Nodes.RaiseStatNode(pos, 
            exc_type = exc_type, 
            exc_value = exc_value, 
            exc_tb = exc_tb, 
            cause = cause) 
    else: 
        return Nodes.ReraiseStatNode(pos) 
 

def p_import_statement(s): 
    # s.sy in ('import', 'cimport') 
    pos = s.position() 
    kind = s.sy 
    s.next() 
    items = [p_dotted_name(s, as_allowed=1)]
    while s.sy == ',': 
        s.next() 
        items.append(p_dotted_name(s, as_allowed=1))
    stats = [] 
    is_absolute = Future.absolute_import in s.context.future_directives
    for pos, target_name, dotted_name, as_name in items: 
        if kind == 'cimport': 
            stat = Nodes.CImportStatNode(
                pos,
                module_name=dotted_name,
                as_name=as_name,
                is_absolute=is_absolute)
        else: 
            if as_name and "." in dotted_name: 
                name_list = ExprNodes.ListNode(pos, args=[
                    ExprNodes.IdentifierStringNode(pos, value=s.context.intern_ustring("*"))])
            else: 
                name_list = None 
            stat = Nodes.SingleAssignmentNode(
                pos,
                lhs=ExprNodes.NameNode(pos, name=as_name or target_name),
                rhs=ExprNodes.ImportNode(
                    pos,
                    module_name=ExprNodes.IdentifierStringNode(pos, value=dotted_name),
                    level=0 if is_absolute else None,
                    name_list=name_list))
        stats.append(stat) 
    return Nodes.StatListNode(pos, stats=stats)
 

def p_from_import_statement(s, first_statement = 0): 
    # s.sy == 'from' 
    pos = s.position() 
    s.next() 
    if s.sy == '.': 
        # count relative import level 
        level = 0 
        while s.sy == '.': 
            level += 1 
            s.next() 
    else: 
        level = None 
    if level is not None and s.sy in ('import', 'cimport'): 
        # we are dealing with "from .. import foo, bar" 
        dotted_name_pos, dotted_name = s.position(), s.context.intern_ustring('')
    else: 
        if level is None and Future.absolute_import in s.context.future_directives: 
            level = 0 
        (dotted_name_pos, _, dotted_name, _) = p_dotted_name(s, as_allowed=False) 
    if s.sy not in ('import', 'cimport'): 
        s.error("Expected 'import' or 'cimport'") 
    kind = s.sy 
    s.next() 
 
    is_cimport = kind == 'cimport' 
    is_parenthesized = False 
    if s.sy == '*': 
        imported_names = [(s.position(), s.context.intern_ustring("*"), None, None)]
        s.next() 
    else: 
        if s.sy == '(': 
            is_parenthesized = True 
            s.next() 
        imported_names = [p_imported_name(s, is_cimport)] 
    while s.sy == ',': 
        s.next() 
        if is_parenthesized and s.sy == ')': 
            break 
        imported_names.append(p_imported_name(s, is_cimport)) 
    if is_parenthesized: 
        s.expect(')') 
    if dotted_name == '__future__': 
        if not first_statement: 
            s.error("from __future__ imports must occur at the beginning of the file") 
        elif level: 
            s.error("invalid syntax") 
        else: 
            for (name_pos, name, as_name, kind) in imported_names: 
                if name == "braces": 
                    s.error("not a chance", name_pos) 
                    break 
                try: 
                    directive = getattr(Future, name) 
                except AttributeError: 
                    s.error("future feature %s is not defined" % name, name_pos) 
                    break 
                s.context.future_directives.add(directive) 
        return Nodes.PassStatNode(pos) 
    elif kind == 'cimport': 
        return Nodes.FromCImportStatNode( 
            pos, module_name=dotted_name, 
            relative_level=level, 
            imported_names=imported_names) 
    else: 
        imported_name_strings = [] 
        items = [] 
        for (name_pos, name, as_name, kind) in imported_names: 
            imported_name_strings.append( 
                ExprNodes.IdentifierStringNode(name_pos, value=name))
            items.append( 
                (name, ExprNodes.NameNode(name_pos, name=as_name or name)))
        import_list = ExprNodes.ListNode( 
            imported_names[0][0], args=imported_name_strings)
        return Nodes.FromImportStatNode(pos, 
            module = ExprNodes.ImportNode(dotted_name_pos, 
                module_name = ExprNodes.IdentifierStringNode(pos, value = dotted_name), 
                level = level, 
                name_list = import_list), 
            items = items) 
 
 
imported_name_kinds = cython.declare(set, set(['class', 'struct', 'union']))

def p_imported_name(s, is_cimport): 
    pos = s.position() 
    kind = None 
    if is_cimport and s.systring in imported_name_kinds: 
        kind = s.systring 
        s.next() 
    name = p_ident(s) 
    as_name = p_as_name(s) 
    return (pos, name, as_name, kind) 
 

def p_dotted_name(s, as_allowed): 
    pos = s.position() 
    target_name = p_ident(s) 
    as_name = None 
    names = [target_name] 
    while s.sy == '.': 
        s.next() 
        names.append(p_ident(s)) 
    if as_allowed: 
        as_name = p_as_name(s) 
    return (pos, target_name, s.context.intern_ustring(u'.'.join(names)), as_name)
 

def p_as_name(s): 
    if s.sy == 'IDENT' and s.systring == 'as': 
        s.next() 
        return p_ident(s) 
    else: 
        return None 
 

def p_assert_statement(s): 
    # s.sy == 'assert' 
    pos = s.position() 
    s.next() 
    cond = p_test(s) 
    if s.sy == ',': 
        s.next() 
        value = p_test(s) 
    else: 
        value = None 
    return Nodes.AssertStatNode(pos, cond = cond, value = value) 
 

statement_terminators = cython.declare(set, set([';', 'NEWLINE', 'EOF'])) 
 
def p_if_statement(s): 
    # s.sy == 'if' 
    pos = s.position() 
    s.next() 
    if_clauses = [p_if_clause(s)] 
    while s.sy == 'elif': 
        s.next() 
        if_clauses.append(p_if_clause(s)) 
    else_clause = p_else_clause(s) 
    return Nodes.IfStatNode(pos, 
        if_clauses = if_clauses, else_clause = else_clause) 
 
def p_if_clause(s): 
    pos = s.position() 
    test = p_test(s) 
    body = p_suite(s) 
    return Nodes.IfClauseNode(pos, 
        condition = test, body = body) 
 
def p_else_clause(s): 
    if s.sy == 'else': 
        s.next() 
        return p_suite(s) 
    else: 
        return None 
 
def p_while_statement(s): 
    # s.sy == 'while' 
    pos = s.position() 
    s.next() 
    test = p_test(s) 
    body = p_suite(s) 
    else_clause = p_else_clause(s) 
    return Nodes.WhileStatNode(pos, 
        condition = test, body = body, 
        else_clause = else_clause) 
 

def p_for_statement(s, is_async=False):
    # s.sy == 'for' 
    pos = s.position() 
    s.next() 
    kw = p_for_bounds(s, allow_testlist=True, is_async=is_async)
    body = p_suite(s) 
    else_clause = p_else_clause(s) 
    kw.update(body=body, else_clause=else_clause, is_async=is_async)
    return Nodes.ForStatNode(pos, **kw) 
 

def p_for_bounds(s, allow_testlist=True, is_async=False):
    target = p_for_target(s) 
    if s.sy == 'in': 
        s.next() 
        iterator = p_for_iterator(s, allow_testlist, is_async=is_async)
        return dict(target=target, iterator=iterator)
    elif not s.in_python_file and not is_async:
        if s.sy == 'from': 
            s.next() 
            bound1 = p_bit_expr(s) 
        else: 
            # Support shorter "for a <= x < b" syntax 
            bound1, target = target, None 
        rel1 = p_for_from_relation(s) 
        name2_pos = s.position() 
        name2 = p_ident(s) 
        rel2_pos = s.position() 
        rel2 = p_for_from_relation(s) 
        bound2 = p_bit_expr(s) 
        step = p_for_from_step(s) 
        if target is None: 
            target = ExprNodes.NameNode(name2_pos, name = name2) 
        else: 
            if not target.is_name: 
                error(target.pos, 
                    "Target of for-from statement must be a variable name") 
            elif name2 != target.name: 
                error(name2_pos, 
                    "Variable name in for-from range does not match target") 
        if rel1[0] != rel2[0]: 
            error(rel2_pos, 
                "Relation directions in for-from do not match") 
        return dict(target = target, 
                    bound1 = bound1, 
                    relation1 = rel1, 
                    relation2 = rel2, 
                    bound2 = bound2, 
                    step = step, 
                    ) 
    else: 
        s.expect('in') 
        return {} 
 
def p_for_from_relation(s): 
    if s.sy in inequality_relations: 
        op = s.sy 
        s.next() 
        return op 
    else: 
        s.error("Expected one of '<', '<=', '>' '>='") 
 
def p_for_from_step(s): 
    if s.sy == 'IDENT' and s.systring == 'by': 
        s.next() 
        step = p_bit_expr(s) 
        return step 
    else: 
        return None 
 
inequality_relations = cython.declare(set, set(['<', '<=', '>', '>='])) 
 
def p_target(s, terminator): 
    pos = s.position() 
    expr = p_starred_expr(s) 
    if s.sy == ',': 
        s.next() 
        exprs = [expr] 
        while s.sy != terminator: 
            exprs.append(p_starred_expr(s)) 
            if s.sy != ',': 
                break 
            s.next() 
        return ExprNodes.TupleNode(pos, args = exprs) 
    else: 
        return expr 
 

def p_for_target(s): 
    return p_target(s, 'in') 
 

def p_for_iterator(s, allow_testlist=True, is_async=False):
    pos = s.position() 
    if allow_testlist: 
        expr = p_testlist(s) 
    else: 
        expr = p_or_test(s) 
    return (ExprNodes.AsyncIteratorNode if is_async else ExprNodes.IteratorNode)(pos, sequence=expr)
 

def p_try_statement(s): 
    # s.sy == 'try' 
    pos = s.position() 
    s.next() 
    body = p_suite(s) 
    except_clauses = [] 
    else_clause = None 
    if s.sy in ('except', 'else'): 
        while s.sy == 'except': 
            except_clauses.append(p_except_clause(s)) 
        if s.sy == 'else': 
            s.next() 
            else_clause = p_suite(s) 
        body = Nodes.TryExceptStatNode(pos, 
            body = body, except_clauses = except_clauses, 
            else_clause = else_clause) 
        if s.sy != 'finally': 
            return body 
        # try-except-finally is equivalent to nested try-except/try-finally 
    if s.sy == 'finally': 
        s.next() 
        finally_clause = p_suite(s) 
        return Nodes.TryFinallyStatNode(pos, 
            body = body, finally_clause = finally_clause) 
    else: 
        s.error("Expected 'except' or 'finally'") 
 
def p_except_clause(s): 
    # s.sy == 'except' 
    pos = s.position() 
    s.next() 
    exc_type = None 
    exc_value = None 
    is_except_as = False 
    if s.sy != ':': 
        exc_type = p_test(s) 
        # normalise into list of single exception tests 
        if isinstance(exc_type, ExprNodes.TupleNode): 
            exc_type = exc_type.args 
        else: 
            exc_type = [exc_type] 
        if s.sy == ',' or (s.sy == 'IDENT' and s.systring == 'as' 
                           and s.context.language_level == 2): 
            s.next() 
            exc_value = p_test(s) 
        elif s.sy == 'IDENT' and s.systring == 'as': 
            # Py3 syntax requires a name here 
            s.next() 
            pos2 = s.position() 
            name = p_ident(s) 
            exc_value = ExprNodes.NameNode(pos2, name = name) 
            is_except_as = True 
    body = p_suite(s) 
    return Nodes.ExceptClauseNode(pos, 
        pattern = exc_type, target = exc_value, 
        body = body, is_except_as=is_except_as) 
 
def p_include_statement(s, ctx): 
    pos = s.position() 
    s.next() # 'include' 
    unicode_include_file_name = p_string_literal(s, 'u')[2] 
    s.expect_newline("Syntax error in include statement") 
    if s.compile_time_eval: 
        include_file_name = unicode_include_file_name 
        include_file_path = s.context.find_include_file(include_file_name, pos) 
        if include_file_path: 
            s.included_files.append(include_file_name) 
            with Utils.open_source_file(include_file_path) as f:
                if Options.source_root:
                    import os
                    rel_path = os.path.relpath(include_file_path, Options.source_root)
                else:
                    rel_path = None
                source_desc = FileSourceDescriptor(include_file_path, rel_path)
                s2 = PyrexScanner(f, source_desc, s, source_encoding=f.encoding, parse_comments=s.parse_comments)
                tree = p_statement_list(s2, ctx) 
            return tree 
        else: 
            return None 
    else: 
        return Nodes.PassStatNode(pos) 
 

def p_with_statement(s): 
    s.next()  # 'with'
    if s.systring == 'template' and not s.in_python_file: 
        node = p_with_template(s) 
    else: 
        node = p_with_items(s) 
    return node 
 

def p_with_items(s, is_async=False):
    pos = s.position() 
    if not s.in_python_file and s.sy == 'IDENT' and s.systring in ('nogil', 'gil'): 
        if is_async:
            s.error("with gil/nogil cannot be async")
        state = s.systring 
        s.next() 
        if s.sy == ',': 
            s.next() 
            body = p_with_items(s) 
        else: 
            body = p_suite(s) 
        return Nodes.GILStatNode(pos, state=state, body=body)
    else: 
        manager = p_test(s) 
        target = None 
        if s.sy == 'IDENT' and s.systring == 'as': 
            s.next() 
            target = p_starred_expr(s) 
        if s.sy == ',': 
            s.next() 
            body = p_with_items(s, is_async=is_async)
        else: 
            body = p_suite(s) 
    return Nodes.WithStatNode(pos, manager=manager, target=target, body=body, is_async=is_async)
 

def p_with_template(s): 
    pos = s.position() 
    templates = [] 
    s.next() 
    s.expect('[') 
    templates.append(s.systring) 
    s.next() 
    while s.systring == ',': 
        s.next() 
        templates.append(s.systring) 
        s.next() 
    s.expect(']') 
    if s.sy == ':': 
        s.next() 
        s.expect_newline("Syntax error in template function declaration") 
        s.expect_indent() 
        body_ctx = Ctx() 
        body_ctx.templates = templates 
        func_or_var = p_c_func_or_var_declaration(s, pos, body_ctx) 
        s.expect_dedent() 
        return func_or_var 
    else: 
        error(pos, "Syntax error in template function declaration") 
 
def p_simple_statement(s, first_statement = 0): 
    #print "p_simple_statement:", s.sy, s.systring ### 
    if s.sy == 'global': 
        node = p_global_statement(s) 
    elif s.sy == 'nonlocal': 
        node = p_nonlocal_statement(s) 
    elif s.sy == 'print': 
        node = p_print_statement(s) 
    elif s.sy == 'exec': 
        node = p_exec_statement(s) 
    elif s.sy == 'del': 
        node = p_del_statement(s) 
    elif s.sy == 'break': 
        node = p_break_statement(s) 
    elif s.sy == 'continue': 
        node = p_continue_statement(s) 
    elif s.sy == 'return': 
        node = p_return_statement(s) 
    elif s.sy == 'raise': 
        node = p_raise_statement(s) 
    elif s.sy in ('import', 'cimport'): 
        node = p_import_statement(s) 
    elif s.sy == 'from': 
        node = p_from_import_statement(s, first_statement = first_statement) 
    elif s.sy == 'yield': 
        node = p_yield_statement(s) 
    elif s.sy == 'assert': 
        node = p_assert_statement(s) 
    elif s.sy == 'pass': 
        node = p_pass_statement(s) 
    else: 
        node = p_expression_or_assignment(s) 
    return node 
 
def p_simple_statement_list(s, ctx, first_statement = 0): 
    # Parse a series of simple statements on one line 
    # separated by semicolons. 
    stat = p_simple_statement(s, first_statement = first_statement) 
    pos = stat.pos 
    stats = [] 
    if not isinstance(stat, Nodes.PassStatNode): 
        stats.append(stat) 
    while s.sy == ';': 
        #print "p_simple_statement_list: maybe more to follow" ### 
        s.next() 
        if s.sy in ('NEWLINE', 'EOF'): 
            break 
        stat = p_simple_statement(s, first_statement = first_statement) 
        if isinstance(stat, Nodes.PassStatNode): 
            continue 
        stats.append(stat) 
        first_statement = False 
 
    if not stats: 
        stat = Nodes.PassStatNode(pos) 
    elif len(stats) == 1: 
        stat = stats[0] 
    else: 
        stat = Nodes.StatListNode(pos, stats = stats) 

    if s.sy not in ('NEWLINE', 'EOF'):
        # provide a better error message for users who accidentally write Cython code in .py files
        if isinstance(stat, Nodes.ExprStatNode):
            if stat.expr.is_name and stat.expr.name == 'cdef':
                s.error("The 'cdef' keyword is only allowed in Cython files (pyx/pxi/pxd)", pos)
    s.expect_newline("Syntax error in simple statement list") 

    return stat 
 
def p_compile_time_expr(s): 
    old = s.compile_time_expr 
    s.compile_time_expr = 1 
    expr = p_testlist(s) 
    s.compile_time_expr = old 
    return expr 
 
def p_DEF_statement(s): 
    pos = s.position() 
    denv = s.compile_time_env 
    s.next() # 'DEF' 
    name = p_ident(s) 
    s.expect('=') 
    expr = p_compile_time_expr(s) 
    if s.compile_time_eval:
        value = expr.compile_time_value(denv)
        #print "p_DEF_statement: %s = %r" % (name, value) ###
        denv.declare(name, value)
    s.expect_newline("Expected a newline", ignore_semicolon=True) 
    return Nodes.PassStatNode(pos) 
 
def p_IF_statement(s, ctx): 
    pos = s.position() 
    saved_eval = s.compile_time_eval 
    current_eval = saved_eval 
    denv = s.compile_time_env 
    result = None 
    while 1: 
        s.next() # 'IF' or 'ELIF' 
        expr = p_compile_time_expr(s) 
        s.compile_time_eval = current_eval and bool(expr.compile_time_value(denv)) 
        body = p_suite(s, ctx) 
        if s.compile_time_eval: 
            result = body 
            current_eval = 0 
        if s.sy != 'ELIF': 
            break 
    if s.sy == 'ELSE': 
        s.next() 
        s.compile_time_eval = current_eval 
        body = p_suite(s, ctx) 
        if current_eval: 
            result = body 
    if not result: 
        result = Nodes.PassStatNode(pos) 
    s.compile_time_eval = saved_eval 
    return result 
 
def p_statement(s, ctx, first_statement = 0): 
    cdef_flag = ctx.cdef_flag 
    decorators = None 
    if s.sy == 'ctypedef': 
        if ctx.level not in ('module', 'module_pxd'): 
            s.error("ctypedef statement not allowed here") 
        #if ctx.api: 
        #    error(s.position(), "'api' not allowed with 'ctypedef'") 
        return p_ctypedef_statement(s, ctx) 
    elif s.sy == 'DEF': 
        return p_DEF_statement(s) 
    elif s.sy == 'IF': 
        return p_IF_statement(s, ctx) 
    elif s.sy == '@': 
        if ctx.level not in ('module', 'class', 'c_class', 'function', 'property', 'module_pxd', 'c_class_pxd', 'other'): 
            s.error('decorator not allowed here') 
        s.level = ctx.level 
        decorators = p_decorators(s) 
        if not ctx.allow_struct_enum_decorator and s.sy not in ('def', 'cdef', 'cpdef', 'class', 'async'):
            if s.sy == 'IDENT' and s.systring == 'async':
                pass  # handled below
            else:
                s.error("Decorators can only be followed by functions or classes")
    elif s.sy == 'pass' and cdef_flag: 
        # empty cdef block 
        return p_pass_statement(s, with_newline=1)
 
    overridable = 0 
    if s.sy == 'cdef': 
        cdef_flag = 1 
        s.next() 
    elif s.sy == 'cpdef': 
        cdef_flag = 1 
        overridable = 1 
        s.next() 
    if cdef_flag: 
        if ctx.level not in ('module', 'module_pxd', 'function', 'c_class', 'c_class_pxd'): 
            s.error('cdef statement not allowed here') 
        s.level = ctx.level 
        node = p_cdef_statement(s, ctx(overridable=overridable))
        if decorators is not None: 
            tup = (Nodes.CFuncDefNode, Nodes.CVarDefNode, Nodes.CClassDefNode)
            if ctx.allow_struct_enum_decorator: 
                tup += (Nodes.CStructOrUnionDefNode, Nodes.CEnumDefNode)
            if not isinstance(node, tup): 
                s.error("Decorators can only be followed by functions or classes") 
            node.decorators = decorators 
        return node 
    else: 
        if ctx.api: 
            s.error("'api' not allowed with this statement", fatal=False) 
        elif s.sy == 'def': 
            # def statements aren't allowed in pxd files, except 
            # as part of a cdef class 
            if ('pxd' in ctx.level) and (ctx.level != 'c_class_pxd'): 
                s.error('def statement not allowed here') 
            s.level = ctx.level 
            return p_def_statement(s, decorators) 
        elif s.sy == 'class': 
            if ctx.level not in ('module', 'function', 'class', 'other'): 
                s.error("class definition not allowed here") 
            return p_class_statement(s, decorators) 
        elif s.sy == 'include': 
            if ctx.level not in ('module', 'module_pxd'): 
                s.error("include statement not allowed here") 
            return p_include_statement(s, ctx) 
        elif ctx.level == 'c_class' and s.sy == 'IDENT' and s.systring == 'property': 
            return p_property_decl(s) 
        elif s.sy == 'pass' and ctx.level != 'property': 
            return p_pass_statement(s, with_newline=True) 
        else: 
            if ctx.level in ('c_class_pxd', 'property'): 
                node = p_ignorable_statement(s) 
                if node is not None: 
                    return node 
                s.error("Executable statement not allowed here") 
            if s.sy == 'if': 
                return p_if_statement(s) 
            elif s.sy == 'while': 
                return p_while_statement(s) 
            elif s.sy == 'for': 
                return p_for_statement(s) 
            elif s.sy == 'try': 
                return p_try_statement(s) 
            elif s.sy == 'with': 
                return p_with_statement(s) 
            elif s.sy == 'async':
                s.next()
                return p_async_statement(s, ctx, decorators)
            else: 
                if s.sy == 'IDENT' and s.systring == 'async':
                    ident_name = s.systring
                    # PEP 492 enables the async/await keywords when it spots "async def ..."
                    s.next()
                    if s.sy == 'def':
                        return p_async_statement(s, ctx, decorators)
                    elif decorators:
                        s.error("Decorators can only be followed by functions or classes")
                    s.put_back('IDENT', ident_name)  # re-insert original token
                return p_simple_statement_list(s, ctx, first_statement=first_statement)
 

def p_statement_list(s, ctx, first_statement = 0): 
    # Parse a series of statements separated by newlines. 
    pos = s.position() 
    stats = [] 
    while s.sy not in ('DEDENT', 'EOF'): 
        stat = p_statement(s, ctx, first_statement = first_statement) 
        if isinstance(stat, Nodes.PassStatNode): 
            continue 
        stats.append(stat) 
        first_statement = False 
    if not stats: 
        return Nodes.PassStatNode(pos) 
    elif len(stats) == 1: 
        return stats[0] 
    else: 
        return Nodes.StatListNode(pos, stats = stats) 
 
 
def p_suite(s, ctx=Ctx()): 
    return p_suite_with_docstring(s, ctx, with_doc_only=False)[1] 
 
 
def p_suite_with_docstring(s, ctx, with_doc_only=False): 
    s.expect(':') 
    doc = None 
    if s.sy == 'NEWLINE': 
        s.next() 
        s.expect_indent() 
        if with_doc_only: 
            doc = p_doc_string(s) 
        body = p_statement_list(s, ctx) 
        s.expect_dedent() 
    else: 
        if ctx.api: 
            s.error("'api' not allowed with this statement", fatal=False) 
        if ctx.level in ('module', 'class', 'function', 'other'): 
            body = p_simple_statement_list(s, ctx) 
        else: 
            body = p_pass_statement(s) 
            s.expect_newline("Syntax error in declarations", ignore_semicolon=True) 
    if not with_doc_only: 
        doc, body = _extract_docstring(body) 
    return doc, body 
 
 
def p_positional_and_keyword_args(s, end_sy_set, templates = None): 
    """ 
    Parses positional and keyword arguments. end_sy_set 
    should contain any s.sy that terminate the argument list. 
    Argument expansion (* and **) are not allowed. 
 
    Returns: (positional_args, keyword_args) 
    """ 
    positional_args = [] 
    keyword_args = [] 
    pos_idx = 0 
 
    while s.sy not in end_sy_set: 
        if s.sy == '*' or s.sy == '**': 
            s.error('Argument expansion not allowed here.', fatal=False) 
 
        parsed_type = False 
        if s.sy == 'IDENT' and s.peek()[0] == '=': 
            ident = s.systring 
            s.next() # s.sy is '=' 
            s.next() 
            if looking_at_expr(s): 
                arg = p_test(s) 
            else: 
                base_type = p_c_base_type(s, templates = templates) 
                declarator = p_c_declarator(s, empty = 1) 
                arg = Nodes.CComplexBaseTypeNode(base_type.pos, 
                    base_type = base_type, declarator = declarator) 
                parsed_type = True 
            keyword_node = ExprNodes.IdentifierStringNode(arg.pos, value=ident)
            keyword_args.append((keyword_node, arg)) 
            was_keyword = True 
 
        else: 
            if looking_at_expr(s): 
                arg = p_test(s) 
            else: 
                base_type = p_c_base_type(s, templates = templates) 
                declarator = p_c_declarator(s, empty = 1) 
                arg = Nodes.CComplexBaseTypeNode(base_type.pos, 
                    base_type = base_type, declarator = declarator) 
                parsed_type = True 
            positional_args.append(arg) 
            pos_idx += 1 
            if len(keyword_args) > 0: 
                s.error("Non-keyword arg following keyword arg", 
                        pos=arg.pos) 
 
        if s.sy != ',': 
            if s.sy not in end_sy_set: 
                if parsed_type: 
                    s.error("Unmatched %s" % " or ".join(end_sy_set)) 
            break 
        s.next() 
    return positional_args, keyword_args 
 
def p_c_base_type(s, self_flag = 0, nonempty = 0, templates = None): 
    # If self_flag is true, this is the base type for the 
    # self argument of a C method of an extension type. 
    if s.sy == '(': 
        return p_c_complex_base_type(s, templates = templates) 
    else: 
        return p_c_simple_base_type(s, self_flag, nonempty = nonempty, templates = templates) 
 
def p_calling_convention(s): 
    if s.sy == 'IDENT' and s.systring in calling_convention_words: 
        result = s.systring 
        s.next() 
        return result 
    else: 
        return "" 
 

calling_convention_words = cython.declare( 
    set, set(["__stdcall", "__cdecl", "__fastcall"])) 
 

def p_c_complex_base_type(s, templates = None): 
    # s.sy == '(' 
    pos = s.position() 
    s.next() 
    base_type = p_c_base_type(s, templates=templates)
    declarator = p_c_declarator(s, empty=True)
    type_node = Nodes.CComplexBaseTypeNode(
        pos, base_type=base_type, declarator=declarator)
    if s.sy == ',':
        components = [type_node]
        while s.sy == ',':
            s.next()
            if s.sy == ')':
                break
            base_type = p_c_base_type(s, templates=templates)
            declarator = p_c_declarator(s, empty=True)
            components.append(Nodes.CComplexBaseTypeNode(
                pos, base_type=base_type, declarator=declarator))
        type_node = Nodes.CTupleBaseTypeNode(pos, components = components)

    s.expect(')') 
    if s.sy == '[': 
        if is_memoryviewslice_access(s): 
            type_node = p_memoryviewslice_access(s, type_node) 
        else: 
            type_node = p_buffer_or_template(s, type_node, templates) 
    return type_node 
 
 
def p_c_simple_base_type(s, self_flag, nonempty, templates = None): 
    #print "p_c_simple_base_type: self_flag =", self_flag, nonempty 
    is_basic = 0 
    signed = 1 
    longness = 0 
    complex = 0 
    module_path = [] 
    pos = s.position() 
    if not s.sy == 'IDENT': 
        error(pos, "Expected an identifier, found '%s'" % s.sy) 
    if s.systring == 'const': 
        s.next() 
        base_type = p_c_base_type(s, self_flag=self_flag, nonempty=nonempty, templates=templates)
        if isinstance(base_type, Nodes.MemoryViewSliceTypeNode):
            # reverse order to avoid having to write "(const int)[:]"
            base_type.base_type_node = Nodes.CConstTypeNode(pos, base_type=base_type.base_type_node)
            return base_type
        return Nodes.CConstTypeNode(pos, base_type=base_type)
    if looking_at_base_type(s): 
        #print "p_c_simple_base_type: looking_at_base_type at", s.position() 
        is_basic = 1 
        if s.sy == 'IDENT' and s.systring in special_basic_c_types: 
            signed, longness = special_basic_c_types[s.systring] 
            name = s.systring 
            s.next() 
        else: 
            signed, longness = p_sign_and_longness(s) 
            if s.sy == 'IDENT' and s.systring in basic_c_type_names: 
                name = s.systring 
                s.next() 
            else: 
                name = 'int'  # long [int], short [int], long [int] complex, etc. 
        if s.sy == 'IDENT' and s.systring == 'complex': 
            complex = 1 
            s.next() 
    elif looking_at_dotted_name(s): 
        #print "p_c_simple_base_type: looking_at_type_name at", s.position() 
        name = s.systring 
        s.next() 
        while s.sy == '.': 
            module_path.append(name) 
            s.next() 
            name = p_ident(s) 
    else: 
        name = s.systring 
        s.next() 
        if nonempty and s.sy != 'IDENT': 
            # Make sure this is not a declaration of a variable or function. 
            if s.sy == '(': 
                s.next() 
                if (s.sy == '*' or s.sy == '**' or s.sy == '&' 
                        or (s.sy == 'IDENT' and s.systring in calling_convention_words)): 
                    s.put_back('(', '(') 
                else: 
                    s.put_back('(', '(') 
                    s.put_back('IDENT', name) 
                    name = None 
            elif s.sy not in ('*', '**', '[', '&'): 
                s.put_back('IDENT', name) 
                name = None 
 
    type_node = Nodes.CSimpleBaseTypeNode(pos, 
        name = name, module_path = module_path, 
        is_basic_c_type = is_basic, signed = signed, 
        complex = complex, longness = longness, 
        is_self_arg = self_flag, templates = templates) 
 
    #    declarations here. 
    if s.sy == '[': 
        if is_memoryviewslice_access(s): 
            type_node = p_memoryviewslice_access(s, type_node) 
        else: 
            type_node = p_buffer_or_template(s, type_node, templates) 
 
    if s.sy == '.': 
        s.next() 
        name = p_ident(s) 
        type_node = Nodes.CNestedBaseTypeNode(pos, base_type = type_node, name = name) 
 
    return type_node 
 
def p_buffer_or_template(s, base_type_node, templates): 
    # s.sy == '[' 
    pos = s.position() 
    s.next() 
    # Note that buffer_positional_options_count=1, so the only positional argument is dtype. 
    # For templated types, all parameters are types. 
    positional_args, keyword_args = ( 
        p_positional_and_keyword_args(s, (']',), templates) 
    ) 
    s.expect(']') 
 
    if s.sy == '[': 
        base_type_node = p_buffer_or_template(s, base_type_node, templates) 
 
    keyword_dict = ExprNodes.DictNode(pos, 
        key_value_pairs = [ 
            ExprNodes.DictItemNode(pos=key.pos, key=key, value=value) 
            for key, value in keyword_args 
        ]) 
    result = Nodes.TemplatedTypeNode(pos, 
        positional_args = positional_args, 
        keyword_args = keyword_dict, 
        base_type_node = base_type_node) 
    return result 
 
def p_bracketed_base_type(s, base_type_node, nonempty, empty): 
    # s.sy == '[' 
    if empty and not nonempty: 
        # sizeof-like thing.  Only anonymous C arrays allowed (int[SIZE]). 
        return base_type_node 
    elif not empty and nonempty: 
        # declaration of either memoryview slice or buffer. 
        if is_memoryviewslice_access(s): 
            return p_memoryviewslice_access(s, base_type_node) 
        else: 
            return p_buffer_or_template(s, base_type_node, None) 
            # return p_buffer_access(s, base_type_node) 
    elif not empty and not nonempty: 
        # only anonymous C arrays and memoryview slice arrays here.  We 
        # disallow buffer declarations for now, due to ambiguity with anonymous 
        # C arrays. 
        if is_memoryviewslice_access(s): 
            return p_memoryviewslice_access(s, base_type_node) 
        else: 
            return base_type_node 
 
def is_memoryviewslice_access(s): 
    # s.sy == '[' 
    # a memoryview slice declaration is distinguishable from a buffer access 
    # declaration by the first entry in the bracketed list.  The buffer will 
    # not have an unnested colon in the first entry; the memoryview slice will. 
    saved = [(s.sy, s.systring)] 
    s.next() 
    retval = False 
    if s.systring == ':': 
        retval = True 
    elif s.sy == 'INT': 
        saved.append((s.sy, s.systring)) 
        s.next() 
        if s.sy == ':': 
            retval = True 
 
    for sv in saved[::-1]: 
        s.put_back(*sv) 
 
    return retval 
 
def p_memoryviewslice_access(s, base_type_node): 
    # s.sy == '[' 
    pos = s.position() 
    s.next() 
    subscripts, _ = p_subscript_list(s) 
    # make sure each entry in subscripts is a slice 
    for subscript in subscripts: 
        if len(subscript) < 2: 
            s.error("An axis specification in memoryview declaration does not have a ':'.") 
    s.expect(']') 
    indexes = make_slice_nodes(pos, subscripts) 
    result = Nodes.MemoryViewSliceTypeNode(pos, 
            base_type_node = base_type_node, 
            axes = indexes) 
    return result 
 
def looking_at_name(s): 
    return s.sy == 'IDENT' and not s.systring in calling_convention_words 
 
def looking_at_expr(s): 
    if s.systring in base_type_start_words: 
        return False 
    elif s.sy == 'IDENT': 
        is_type = False 
        name = s.systring 
        dotted_path = [] 
        s.next() 
 
        while s.sy == '.': 
            s.next() 
            dotted_path.append(s.systring) 
            s.expect('IDENT') 
 
        saved = s.sy, s.systring 
        if s.sy == 'IDENT': 
            is_type = True 
        elif s.sy == '*' or s.sy == '**': 
            s.next() 
            is_type = s.sy in (')', ']') 
            s.put_back(*saved) 
        elif s.sy == '(': 
            s.next() 
            is_type = s.sy == '*' 
            s.put_back(*saved) 
        elif s.sy == '[': 
            s.next() 
            is_type = s.sy == ']' or not looking_at_expr(s)  # could be a nested template type
            s.put_back(*saved) 
 
        dotted_path.reverse() 
        for p in dotted_path: 
            s.put_back('IDENT', p) 
            s.put_back('.', '.') 
 
        s.put_back('IDENT', name) 
        return not is_type and saved[0] 
    else: 
        return True 
 
def looking_at_base_type(s): 
    #print "looking_at_base_type?", s.sy, s.systring, s.position() 
    return s.sy == 'IDENT' and s.systring in base_type_start_words 
 
def looking_at_dotted_name(s): 
    if s.sy == 'IDENT': 
        name = s.systring 
        s.next() 
        result = s.sy == '.' 
        s.put_back('IDENT', name) 
        return result 
    else: 
        return 0 
 
def looking_at_call(s): 
    "See if we're looking at a.b.c(" 
    # Don't mess up the original position, so save and restore it. 
    # Unfortunately there's no good way to handle this, as a subsequent call 
    # to next() will not advance the position until it reads a new token. 
    position = s.start_line, s.start_col 
    result = looking_at_expr(s) == u'(' 
    if not result: 
        s.start_line, s.start_col = position 
    return result 
 
basic_c_type_names = cython.declare( 
    set, set(["void", "char", "int", "float", "double", "bint"])) 
 
special_basic_c_types = cython.declare(dict, { 
    # name : (signed, longness) 
    "Py_UNICODE" : (0, 0), 
    "Py_UCS4"    : (0, 0), 
    "Py_hash_t"  : (2, 0),
    "Py_ssize_t" : (2, 0), 
    "ssize_t"    : (2, 0), 
    "size_t"     : (0, 0), 
    "ptrdiff_t"  : (2, 0), 
    "Py_tss_t"   : (1, 0),
}) 
 
sign_and_longness_words = cython.declare( 
    set, set(["short", "long", "signed", "unsigned"])) 
 
base_type_start_words = cython.declare( 
    set, 
    basic_c_type_names 
    | sign_and_longness_words 
    | set(special_basic_c_types)) 
 
struct_enum_union = cython.declare( 
    set, set(["struct", "union", "enum", "packed"])) 
 
def p_sign_and_longness(s): 
    signed = 1 
    longness = 0 
    while s.sy == 'IDENT' and s.systring in sign_and_longness_words: 
        if s.systring == 'unsigned': 
            signed = 0 
        elif s.systring == 'signed': 
            signed = 2 
        elif s.systring == 'short': 
            longness = -1 
        elif s.systring == 'long': 
            longness += 1 
        s.next() 
    return signed, longness 
 
def p_opt_cname(s): 
    literal = p_opt_string_literal(s, 'u') 
    if literal is not None: 
        cname = EncodedString(literal) 
        cname.encoding = s.source_encoding 
    else: 
        cname = None 
    return cname 
 
def p_c_declarator(s, ctx = Ctx(), empty = 0, is_type = 0, cmethod_flag = 0, 
                   assignable = 0, nonempty = 0, 
                   calling_convention_allowed = 0): 
    # If empty is true, the declarator must be empty. If nonempty is true, 
    # the declarator must be nonempty. Otherwise we don't care. 
    # If cmethod_flag is true, then if this declarator declares 
    # a function, it's a C method of an extension type. 
    pos = s.position() 
    if s.sy == '(': 
        s.next() 
        if s.sy == ')' or looking_at_name(s): 
            base = Nodes.CNameDeclaratorNode(pos, name=s.context.intern_ustring(u""), cname=None)
            result = p_c_func_declarator(s, pos, ctx, base, cmethod_flag) 
        else: 
            result = p_c_declarator(s, ctx, empty = empty, is_type = is_type, 
                                    cmethod_flag = cmethod_flag, 
                                    nonempty = nonempty, 
                                    calling_convention_allowed = 1) 
            s.expect(')') 
    else: 
        result = p_c_simple_declarator(s, ctx, empty, is_type, cmethod_flag, 
                                       assignable, nonempty) 
    if not calling_convention_allowed and result.calling_convention and s.sy != '(': 
        error(s.position(), "%s on something that is not a function" 
            % result.calling_convention) 
    while s.sy in ('[', '('): 
        pos = s.position() 
        if s.sy == '[': 
            result = p_c_array_declarator(s, result) 
        else: # sy == '(' 
            s.next() 
            result = p_c_func_declarator(s, pos, ctx, result, cmethod_flag) 
        cmethod_flag = 0 
    return result 
 
def p_c_array_declarator(s, base): 
    pos = s.position() 
    s.next() # '[' 
    if s.sy != ']': 
        dim = p_testlist(s) 
    else: 
        dim = None 
    s.expect(']') 
    return Nodes.CArrayDeclaratorNode(pos, base = base, dimension = dim) 
 
def p_c_func_declarator(s, pos, ctx, base, cmethod_flag): 
    #  Opening paren has already been skipped 
    args = p_c_arg_list(s, ctx, cmethod_flag = cmethod_flag, 
                        nonempty_declarators = 0) 
    ellipsis = p_optional_ellipsis(s) 
    s.expect(')') 
    nogil = p_nogil(s) 
    exc_val, exc_check = p_exception_value_clause(s) 
    with_gil = p_with_gil(s) 
    return Nodes.CFuncDeclaratorNode(pos, 
        base = base, args = args, has_varargs = ellipsis, 
        exception_value = exc_val, exception_check = exc_check, 
        nogil = nogil or ctx.nogil or with_gil, with_gil = with_gil) 
 
supported_overloaded_operators = cython.declare(set, set([ 
    '+', '-', '*', '/', '%', 
    '++', '--', '~', '|', '&', '^', '<<', '>>', ',', 
    '==', '!=', '>=', '>', '<=', '<', 
    '[]', '()', '!', '=',
    'bool',
])) 
 
def p_c_simple_declarator(s, ctx, empty, is_type, cmethod_flag, 
                          assignable, nonempty): 
    pos = s.position() 
    calling_convention = p_calling_convention(s) 
    if s.sy == '*': 
        s.next() 
        if s.systring == 'const': 
            const_pos = s.position() 
            s.next() 
            const_base = p_c_declarator(s, ctx, empty = empty, 
                                       is_type = is_type, 
                                       cmethod_flag = cmethod_flag, 
                                       assignable = assignable, 
                                       nonempty = nonempty) 
            base = Nodes.CConstDeclaratorNode(const_pos, base = const_base) 
        else: 
            base = p_c_declarator(s, ctx, empty = empty, is_type = is_type, 
                                  cmethod_flag = cmethod_flag, 
                                  assignable = assignable, nonempty = nonempty) 
        result = Nodes.CPtrDeclaratorNode(pos, 
            base = base) 
    elif s.sy == '**': # scanner returns this as a single token 
        s.next() 
        base = p_c_declarator(s, ctx, empty = empty, is_type = is_type, 
                              cmethod_flag = cmethod_flag, 
                              assignable = assignable, nonempty = nonempty) 
        result = Nodes.CPtrDeclaratorNode(pos, 
            base = Nodes.CPtrDeclaratorNode(pos, 
                base = base)) 
    elif s.sy == '&': 
        s.next() 
        base = p_c_declarator(s, ctx, empty = empty, is_type = is_type, 
                              cmethod_flag = cmethod_flag, 
                              assignable = assignable, nonempty = nonempty) 
        result = Nodes.CReferenceDeclaratorNode(pos, base = base) 
    else: 
        rhs = None 
        if s.sy == 'IDENT': 
            name = s.systring
            if empty: 
                error(s.position(), "Declarator should be empty") 
            s.next() 
            cname = p_opt_cname(s) 
            if name != 'operator' and s.sy == '=' and assignable: 
                s.next() 
                rhs = p_test(s) 
        else: 
            if nonempty: 
                error(s.position(), "Empty declarator") 
            name = "" 
            cname = None 
        if cname is None and ctx.namespace is not None and nonempty: 
            cname = ctx.namespace + "::" + name 
        if name == 'operator' and ctx.visibility == 'extern' and nonempty: 
            op = s.sy 
            if [1 for c in op if c in '+-*/<=>!%&|([^~,']: 
                s.next() 
                # Handle diphthong operators. 
                if op == '(': 
                    s.expect(')') 
                    op = '()' 
                elif op == '[': 
                    s.expect(']') 
                    op = '[]' 
                elif op in ('-', '+', '|', '&') and s.sy == op: 
                    op *= 2       # ++, --, ... 
                    s.next() 
                elif s.sy == '=': 
                    op += s.sy    # +=, -=, ... 
                    s.next() 
                if op not in supported_overloaded_operators: 
                    s.error("Overloading operator '%s' not yet supported." % op, 
                            fatal=False) 
                name += op 
            elif op == 'IDENT':
                op = s.systring;
                if op not in supported_overloaded_operators:
                    s.error("Overloading operator '%s' not yet supported." % op,
                            fatal=False)
                name = name + ' ' + op
                s.next()
        result = Nodes.CNameDeclaratorNode(pos, 
            name = name, cname = cname, default = rhs) 
    result.calling_convention = calling_convention 
    return result 
 
def p_nogil(s): 
    if s.sy == 'IDENT' and s.systring == 'nogil': 
        s.next() 
        return 1 
    else: 
        return 0 
 
def p_with_gil(s): 
    if s.sy == 'with': 
        s.next() 
        s.expect_keyword('gil') 
        return 1 
    else: 
        return 0 
 
def p_exception_value_clause(s): 
    exc_val = None 
    exc_check = 0 
    if s.sy == 'except': 
        s.next() 
        if s.sy == '*': 
            exc_check = 1 
            s.next() 
        elif s.sy == '+': 
            exc_check = '+' 
            s.next() 
            if s.sy == 'IDENT': 
                name = s.systring 
                s.next() 
                exc_val = p_name(s, name) 
            elif s.sy == '*':
                exc_val = ExprNodes.CharNode(s.position(), value=u'*')
                s.next()
        else: 
            if s.sy == '?': 
                exc_check = 1 
                s.next() 
            exc_val = p_test(s) 
    return exc_val, exc_check 
 
c_arg_list_terminators = cython.declare(set, set(['*', '**', '.', ')', ':']))
 
def p_c_arg_list(s, ctx = Ctx(), in_pyfunc = 0, cmethod_flag = 0, 
                 nonempty_declarators = 0, kw_only = 0, annotated = 1): 
    #  Comma-separated list of C argument declarations, possibly empty. 
    #  May have a trailing comma. 
    args = [] 
    is_self_arg = cmethod_flag 
    while s.sy not in c_arg_list_terminators: 
        args.append(p_c_arg_decl(s, ctx, in_pyfunc, is_self_arg, 
            nonempty = nonempty_declarators, kw_only = kw_only, 
            annotated = annotated)) 
        if s.sy != ',': 
            break 
        s.next() 
        is_self_arg = 0 
    return args 
 
def p_optional_ellipsis(s): 
    if s.sy == '.': 
        expect_ellipsis(s) 
        return 1 
    else: 
        return 0 
 
def p_c_arg_decl(s, ctx, in_pyfunc, cmethod_flag = 0, nonempty = 0, 
                 kw_only = 0, annotated = 1): 
    pos = s.position() 
    not_none = or_none = 0 
    default = None 
    annotation = None 
    if s.in_python_file: 
        # empty type declaration 
        base_type = Nodes.CSimpleBaseTypeNode(pos, 
            name = None, module_path = [], 
            is_basic_c_type = 0, signed = 0, 
            complex = 0, longness = 0, 
            is_self_arg = cmethod_flag, templates = None) 
    else: 
        base_type = p_c_base_type(s, cmethod_flag, nonempty = nonempty) 
    declarator = p_c_declarator(s, ctx, nonempty = nonempty) 
    if s.sy in ('not', 'or') and not s.in_python_file: 
        kind = s.sy 
        s.next() 
        if s.sy == 'IDENT' and s.systring == 'None': 
            s.next() 
        else: 
            s.error("Expected 'None'") 
        if not in_pyfunc: 
            error(pos, "'%s None' only allowed in Python functions" % kind) 
        or_none = kind == 'or' 
        not_none = kind == 'not' 
    if annotated and s.sy == ':': 
        s.next() 
        annotation = p_test(s) 
    if s.sy == '=': 
        s.next() 
        if 'pxd' in ctx.level: 
            if s.sy in ['*', '?']:
                # TODO(github/1736): Make this an error for inline declarations.
                default = ExprNodes.NoneNode(pos)
                s.next()
            elif 'inline' in ctx.modifiers:
                default = p_test(s)
            else:
                error(pos, "default values cannot be specified in pxd files, use ? or *") 
        else: 
            default = p_test(s) 
    return Nodes.CArgDeclNode(pos, 
        base_type = base_type, 
        declarator = declarator, 
        not_none = not_none, 
        or_none = or_none, 
        default = default, 
        annotation = annotation, 
        kw_only = kw_only) 
 
def p_api(s): 
    if s.sy == 'IDENT' and s.systring == 'api': 
        s.next() 
        return 1 
    else: 
        return 0 
 
def p_cdef_statement(s, ctx): 
    pos = s.position() 
    ctx.visibility = p_visibility(s, ctx.visibility) 
    ctx.api = ctx.api or p_api(s) 
    if ctx.api: 
        if ctx.visibility not in ('private', 'public'): 
            error(pos, "Cannot combine 'api' with '%s'" % ctx.visibility) 
    if (ctx.visibility == 'extern') and s.sy == 'from': 
        return p_cdef_extern_block(s, pos, ctx) 
    elif s.sy == 'import': 
        s.next() 
        return p_cdef_extern_block(s, pos, ctx) 
    elif p_nogil(s): 
        ctx.nogil = 1 
        if ctx.overridable: 
            error(pos, "cdef blocks cannot be declared cpdef") 
        return p_cdef_block(s, ctx) 
    elif s.sy == ':': 
        if ctx.overridable: 
            error(pos, "cdef blocks cannot be declared cpdef") 
        return p_cdef_block(s, ctx) 
    elif s.sy == 'class': 
        if ctx.level not in ('module', 'module_pxd'): 
            error(pos, "Extension type definition not allowed here") 
        if ctx.overridable: 
            error(pos, "Extension types cannot be declared cpdef") 
        return p_c_class_definition(s, pos, ctx) 
    elif s.sy == 'IDENT' and s.systring == 'cppclass': 
        return p_cpp_class_definition(s, pos, ctx) 
    elif s.sy == 'IDENT' and s.systring in struct_enum_union: 
        if ctx.level not in ('module', 'module_pxd'): 
            error(pos, "C struct/union/enum definition not allowed here") 
        if ctx.overridable: 
            if s.systring != 'enum': 
                error(pos, "C struct/union cannot be declared cpdef") 
        return p_struct_enum(s, pos, ctx) 
    elif s.sy == 'IDENT' and s.systring == 'fused': 
        return p_fused_definition(s, pos, ctx) 
    else: 
        return p_c_func_or_var_declaration(s, pos, ctx) 
 
def p_cdef_block(s, ctx): 
    return p_suite(s, ctx(cdef_flag = 1)) 
 
def p_cdef_extern_block(s, pos, ctx): 
    if ctx.overridable: 
        error(pos, "cdef extern blocks cannot be declared cpdef") 
    include_file = None 
    s.expect('from') 
    if s.sy == '*': 
        s.next() 
    else: 
        include_file = p_string_literal(s, 'u')[2] 
    ctx = ctx(cdef_flag = 1, visibility = 'extern') 
    if s.systring == "namespace": 
        s.next() 
        ctx.namespace = p_string_literal(s, 'u')[2] 
    if p_nogil(s): 
        ctx.nogil = 1 

    # Use "docstring" as verbatim string to include
    verbatim_include, body = p_suite_with_docstring(s, ctx, True)

    return Nodes.CDefExternNode(pos, 
        include_file = include_file, 
        verbatim_include = verbatim_include,
        body = body, 
        namespace = ctx.namespace) 
 
def p_c_enum_definition(s, pos, ctx): 
    # s.sy == ident 'enum' 
    s.next() 
    if s.sy == 'IDENT': 
        name = s.systring 
        s.next() 
        cname = p_opt_cname(s) 
        if cname is None and ctx.namespace is not None: 
            cname = ctx.namespace + "::" + name 
    else: 
        name = None 
        cname = None 
    items = None 
    s.expect(':') 
    items = [] 
    if s.sy != 'NEWLINE': 
        p_c_enum_line(s, ctx, items) 
    else: 
        s.next() # 'NEWLINE' 
        s.expect_indent() 
        while s.sy not in ('DEDENT', 'EOF'): 
            p_c_enum_line(s, ctx, items) 
        s.expect_dedent() 
    return Nodes.CEnumDefNode( 
        pos, name = name, cname = cname, items = items, 
        typedef_flag = ctx.typedef_flag, visibility = ctx.visibility, 
        create_wrapper = ctx.overridable, 
        api = ctx.api, in_pxd = ctx.level == 'module_pxd') 
 
def p_c_enum_line(s, ctx, items): 
    if s.sy != 'pass': 
        p_c_enum_item(s, ctx, items) 
        while s.sy == ',': 
            s.next() 
            if s.sy in ('NEWLINE', 'EOF'): 
                break 
            p_c_enum_item(s, ctx, items) 
    else: 
        s.next() 
    s.expect_newline("Syntax error in enum item list") 
 
def p_c_enum_item(s, ctx, items): 
    pos = s.position() 
    name = p_ident(s) 
    cname = p_opt_cname(s) 
    if cname is None and ctx.namespace is not None: 
        cname = ctx.namespace + "::" + name 
    value = None 
    if s.sy == '=': 
        s.next() 
        value = p_test(s) 
    items.append(Nodes.CEnumDefItemNode(pos, 
        name = name, cname = cname, value = value)) 
 
def p_c_struct_or_union_definition(s, pos, ctx): 
    packed = False 
    if s.systring == 'packed': 
        packed = True 
        s.next() 
        if s.sy != 'IDENT' or s.systring != 'struct': 
            s.expected('struct') 
    # s.sy == ident 'struct' or 'union' 
    kind = s.systring 
    s.next() 
    name = p_ident(s) 
    cname = p_opt_cname(s) 
    if cname is None and ctx.namespace is not None: 
        cname = ctx.namespace + "::" + name 
    attributes = None 
    if s.sy == ':': 
        s.next() 
        s.expect('NEWLINE') 
        s.expect_indent() 
        attributes = [] 
        body_ctx = Ctx() 
        while s.sy != 'DEDENT': 
            if s.sy != 'pass': 
                attributes.append( 
                    p_c_func_or_var_declaration(s, s.position(), body_ctx)) 
            else: 
                s.next() 
                s.expect_newline("Expected a newline") 
        s.expect_dedent() 
    else: 
        s.expect_newline("Syntax error in struct or union definition") 
    return Nodes.CStructOrUnionDefNode(pos, 
        name = name, cname = cname, kind = kind, attributes = attributes, 
        typedef_flag = ctx.typedef_flag, visibility = ctx.visibility, 
        api = ctx.api, in_pxd = ctx.level == 'module_pxd', packed = packed) 
 
def p_fused_definition(s, pos, ctx): 
    """ 
    c(type)def fused my_fused_type: 
        ... 
    """ 
    # s.systring == 'fused' 
 
    if ctx.level not in ('module', 'module_pxd'): 
        error(pos, "Fused type definition not allowed here") 
 
    s.next() 
    name = p_ident(s) 
 
    s.expect(":") 
    s.expect_newline() 
    s.expect_indent() 
 
    types = [] 
    while s.sy != 'DEDENT': 
        if s.sy != 'pass': 
            #types.append(p_c_declarator(s)) 
            types.append(p_c_base_type(s)) #, nonempty=1)) 
        else: 
            s.next() 
 
        s.expect_newline() 
 
    s.expect_dedent() 
 
    if not types: 
        error(pos, "Need at least one type") 
 
    return Nodes.FusedTypeNode(pos, name=name, types=types) 
 
def p_struct_enum(s, pos, ctx): 
    if s.systring == 'enum': 
        return p_c_enum_definition(s, pos, ctx) 
    else: 
        return p_c_struct_or_union_definition(s, pos, ctx) 
 
def p_visibility(s, prev_visibility): 
    pos = s.position() 
    visibility = prev_visibility 
    if s.sy == 'IDENT' and s.systring in ('extern', 'public', 'readonly'): 
        visibility = s.systring 
        if prev_visibility != 'private' and visibility != prev_visibility: 
            s.error("Conflicting visibility options '%s' and '%s'" 
                % (prev_visibility, visibility), fatal=False) 
        s.next() 
    return visibility 
 
def p_c_modifiers(s): 
    if s.sy == 'IDENT' and s.systring in ('inline',): 
        modifier = s.systring 
        s.next() 
        return [modifier] + p_c_modifiers(s) 
    return [] 
 
def p_c_func_or_var_declaration(s, pos, ctx): 
    cmethod_flag = ctx.level in ('c_class', 'c_class_pxd') 
    modifiers = p_c_modifiers(s) 
    base_type = p_c_base_type(s, nonempty = 1, templates = ctx.templates) 
    declarator = p_c_declarator(s, ctx(modifiers=modifiers), cmethod_flag = cmethod_flag,
                                assignable = 1, nonempty = 1) 
    declarator.overridable = ctx.overridable 
    if s.sy == 'IDENT' and s.systring == 'const' and ctx.level == 'cpp_class': 
        s.next() 
        is_const_method = 1 
    else: 
        is_const_method = 0 
    if s.sy == '->':
        # Special enough to give a better error message and keep going.
        s.error(
            "Return type annotation is not allowed in cdef/cpdef signatures. "
            "Please define it before the function name, as in C signatures.",
            fatal=False)
        s.next()
        p_test(s)  # Keep going, but ignore result.
    if s.sy == ':': 
        if ctx.level not in ('module', 'c_class', 'module_pxd', 'c_class_pxd', 'cpp_class') and not ctx.templates: 
            s.error("C function definition not allowed here") 
        doc, suite = p_suite_with_docstring(s, Ctx(level='function')) 
        result = Nodes.CFuncDefNode(pos, 
            visibility = ctx.visibility, 
            base_type = base_type, 
            declarator = declarator, 
            body = suite, 
            doc = doc, 
            modifiers = modifiers, 
            api = ctx.api, 
            overridable = ctx.overridable, 
            is_const_method = is_const_method) 
    else: 
        #if api: 
        #    s.error("'api' not allowed with variable declaration") 
        if is_const_method: 
            declarator.is_const_method = is_const_method 
        declarators = [declarator] 
        while s.sy == ',': 
            s.next() 
            if s.sy == 'NEWLINE': 
                break 
            declarator = p_c_declarator(s, ctx, cmethod_flag = cmethod_flag, 
                                        assignable = 1, nonempty = 1) 
            declarators.append(declarator) 
        doc_line = s.start_line + 1 
        s.expect_newline("Syntax error in C variable declaration", ignore_semicolon=True) 
        if ctx.level in ('c_class', 'c_class_pxd') and s.start_line == doc_line: 
            doc = p_doc_string(s) 
        else: 
            doc = None 
        result = Nodes.CVarDefNode(pos, 
            visibility = ctx.visibility, 
            base_type = base_type, 
            declarators = declarators, 
            in_pxd = ctx.level in ('module_pxd', 'c_class_pxd'), 
            doc = doc, 
            api = ctx.api, 
            modifiers = modifiers, 
            overridable = ctx.overridable) 
    return result 
 
def p_ctypedef_statement(s, ctx): 
    # s.sy == 'ctypedef' 
    pos = s.position() 
    s.next() 
    visibility = p_visibility(s, ctx.visibility) 
    api = p_api(s) 
    ctx = ctx(typedef_flag = 1, visibility = visibility) 
    if api: 
        ctx.api = 1 
    if s.sy == 'class': 
        return p_c_class_definition(s, pos, ctx) 
    elif s.sy == 'IDENT' and s.systring in struct_enum_union: 
        return p_struct_enum(s, pos, ctx) 
    elif s.sy == 'IDENT' and s.systring == 'fused': 
        return p_fused_definition(s, pos, ctx) 
    else: 
        base_type = p_c_base_type(s, nonempty = 1) 
        declarator = p_c_declarator(s, ctx, is_type = 1, nonempty = 1) 
        s.expect_newline("Syntax error in ctypedef statement", ignore_semicolon=True) 
        return Nodes.CTypeDefNode( 
            pos, base_type = base_type, 
            declarator = declarator, 
            visibility = visibility, api = api, 
            in_pxd = ctx.level == 'module_pxd') 
 
def p_decorators(s): 
    decorators = [] 
    while s.sy == '@': 
        pos = s.position() 
        s.next() 
        decstring = p_dotted_name(s, as_allowed=0)[2] 
        names = decstring.split('.') 
        decorator = ExprNodes.NameNode(pos, name=s.context.intern_ustring(names[0]))
        for name in names[1:]: 
            decorator = ExprNodes.AttributeNode(
                pos, attribute=s.context.intern_ustring(name), obj=decorator)
        if s.sy == '(': 
            decorator = p_call(s, decorator) 
        decorators.append(Nodes.DecoratorNode(pos, decorator=decorator)) 
        s.expect_newline("Expected a newline after decorator") 
    return decorators 
 

def _reject_cdef_modifier_in_py(s, name):
    """Step over incorrectly placed cdef modifiers (@see _CDEF_MODIFIERS) to provide a good error message for them.
    """
    if s.sy == 'IDENT' and name in _CDEF_MODIFIERS:
        # Special enough to provide a good error message.
        s.error("Cannot use cdef modifier '%s' in Python function signature. Use a decorator instead." % name, fatal=False)
        return p_ident(s)  # Keep going, in case there are other errors.
    return name


def p_def_statement(s, decorators=None, is_async_def=False):
    # s.sy == 'def' 
    pos = s.position() 
    # PEP 492 switches the async/await keywords on in "async def" functions
    if is_async_def:
        s.enter_async()
    s.next() 
    name = _reject_cdef_modifier_in_py(s, p_ident(s))
    s.expect(
        '(',
        "Expected '(', found '%s'. Did you use cdef syntax in a Python declaration? "
        "Use decorators and Python type annotations instead." % (
            s.systring if s.sy == 'IDENT' else s.sy))
    args, star_arg, starstar_arg = p_varargslist(s, terminator=')') 
    s.expect(')') 
    _reject_cdef_modifier_in_py(s, s.systring)
    return_type_annotation = None 
    if s.sy == '->': 
        s.next() 
        return_type_annotation = p_test(s) 
        _reject_cdef_modifier_in_py(s, s.systring)

    doc, body = p_suite_with_docstring(s, Ctx(level='function')) 
    if is_async_def:
        s.exit_async()
 
    return Nodes.DefNode(
        pos, name=name, args=args, star_arg=star_arg, starstar_arg=starstar_arg,
        doc=doc, body=body, decorators=decorators, is_async_def=is_async_def,
        return_type_annotation=return_type_annotation)


def p_varargslist(s, terminator=')', annotated=1): 
    args = p_c_arg_list(s, in_pyfunc = 1, nonempty_declarators = 1, 
                        annotated = annotated) 
    star_arg = None 
    starstar_arg = None 
    if s.sy == '*': 
        s.next() 
        if s.sy == 'IDENT': 
            star_arg = p_py_arg_decl(s, annotated=annotated) 
        if s.sy == ',': 
            s.next() 
            args.extend(p_c_arg_list(s, in_pyfunc = 1, 
                nonempty_declarators = 1, kw_only = 1, annotated = annotated)) 
        elif s.sy != terminator: 
            s.error("Syntax error in Python function argument list") 
    if s.sy == '**': 
        s.next() 
        starstar_arg = p_py_arg_decl(s, annotated=annotated) 
    if s.sy == ',':
        s.next()
    return (args, star_arg, starstar_arg) 
 
def p_py_arg_decl(s, annotated = 1): 
    pos = s.position() 
    name = p_ident(s) 
    annotation = None 
    if annotated and s.sy == ':': 
        s.next() 
        annotation = p_test(s) 
    return Nodes.PyArgDeclNode(pos, name = name, annotation = annotation) 
 

def p_class_statement(s, decorators): 
    # s.sy == 'class' 
    pos = s.position() 
    s.next() 
    class_name = EncodedString(p_ident(s))
    class_name.encoding = s.source_encoding  # FIXME: why is this needed?
    arg_tuple = None 
    keyword_dict = None 
    if s.sy == '(': 
        positional_args, keyword_args = p_call_parse_args(s, allow_genexp=False)
        arg_tuple, keyword_dict = p_call_build_packed_args(pos, positional_args, keyword_args)
    if arg_tuple is None: 
        # XXX: empty arg_tuple 
        arg_tuple = ExprNodes.TupleNode(pos, args=[]) 
    doc, body = p_suite_with_docstring(s, Ctx(level='class')) 
    return Nodes.PyClassDefNode( 
        pos, name=class_name, 
        bases=arg_tuple, 
        keyword_args=keyword_dict, 
        doc=doc, body=body, decorators=decorators, 
        force_py3_semantics=s.context.language_level >= 3) 
 

def p_c_class_definition(s, pos,  ctx): 
    # s.sy == 'class' 
    s.next() 
    module_path = [] 
    class_name = p_ident(s) 
    while s.sy == '.': 
        s.next() 
        module_path.append(class_name) 
        class_name = p_ident(s) 
    if module_path and ctx.visibility != 'extern': 
        error(pos, "Qualified class name only allowed for 'extern' C class") 
    if module_path and s.sy == 'IDENT' and s.systring == 'as': 
        s.next() 
        as_name = p_ident(s) 
    else: 
        as_name = class_name 
    objstruct_name = None 
    typeobj_name = None 
    bases = None
    check_size = None
    if s.sy == '(': 
        positional_args, keyword_args = p_call_parse_args(s, allow_genexp=False)
        if keyword_args:
            s.error("C classes cannot take keyword bases.")
        bases, _ = p_call_build_packed_args(pos, positional_args, keyword_args)
    if bases is None:
        bases = ExprNodes.TupleNode(pos, args=[])

    if s.sy == '[': 
        if ctx.visibility not in ('public', 'extern') and not ctx.api: 
            error(s.position(), "Name options only allowed for 'public', 'api', or 'extern' C class") 
        objstruct_name, typeobj_name, check_size = p_c_class_options(s)
    if s.sy == ':': 
        if ctx.level == 'module_pxd': 
            body_level = 'c_class_pxd' 
        else: 
            body_level = 'c_class' 
        doc, body = p_suite_with_docstring(s, Ctx(level=body_level)) 
    else: 
        s.expect_newline("Syntax error in C class definition") 
        doc = None 
        body = None 
    if ctx.visibility == 'extern': 
        if not module_path: 
            error(pos, "Module name required for 'extern' C class") 
        if typeobj_name: 
            error(pos, "Type object name specification not allowed for 'extern' C class") 
    elif ctx.visibility == 'public': 
        if not objstruct_name: 
            error(pos, "Object struct name specification required for 'public' C class") 
        if not typeobj_name: 
            error(pos, "Type object name specification required for 'public' C class") 
    elif ctx.visibility == 'private': 
        if ctx.api: 
            if not objstruct_name: 
                error(pos, "Object struct name specification required for 'api' C class") 
            if not typeobj_name: 
                error(pos, "Type object name specification required for 'api' C class") 
    else: 
        error(pos, "Invalid class visibility '%s'" % ctx.visibility) 
    return Nodes.CClassDefNode(pos, 
        visibility = ctx.visibility, 
        typedef_flag = ctx.typedef_flag, 
        api = ctx.api, 
        module_name = ".".join(module_path), 
        class_name = class_name, 
        as_name = as_name, 
        bases = bases,
        objstruct_name = objstruct_name, 
        typeobj_name = typeobj_name, 
        check_size = check_size,
        in_pxd = ctx.level == 'module_pxd', 
        doc = doc, 
        body = body) 
 

def p_c_class_options(s): 
    objstruct_name = None 
    typeobj_name = None 
    check_size = None
    s.expect('[') 
    while 1: 
        if s.sy != 'IDENT': 
            break 
        if s.systring == 'object': 
            s.next() 
            objstruct_name = p_ident(s) 
        elif s.systring == 'type': 
            s.next() 
            typeobj_name = p_ident(s) 
        elif s.systring == 'check_size':
            s.next()
            check_size = p_ident(s)
            if check_size not in ('ignore', 'warn', 'error'):
                s.error("Expected one of ignore, warn or error, found %r" % check_size)
        if s.sy != ',': 
            break 
        s.next() 
    s.expect(']', "Expected 'object', 'type' or 'check_size'")
    return objstruct_name, typeobj_name, check_size
 
 
def p_property_decl(s): 
    pos = s.position() 
    s.next()  # 'property' 
    name = p_ident(s) 
    doc, body = p_suite_with_docstring( 
        s, Ctx(level='property'), with_doc_only=True) 
    return Nodes.PropertyNode(pos, name=name, doc=doc, body=body) 
 
 
def p_ignorable_statement(s): 
    """ 
    Parses any kind of ignorable statement that is allowed in .pxd files. 
    """ 
    if s.sy == 'BEGIN_STRING': 
        pos = s.position() 
        string_node = p_atom(s) 
        s.expect_newline("Syntax error in string", ignore_semicolon=True) 
        return Nodes.ExprStatNode(pos, expr=string_node) 
    return None 
 
 
def p_doc_string(s): 
    if s.sy == 'BEGIN_STRING': 
        pos = s.position() 
        kind, bytes_result, unicode_result = p_cat_string_literal(s) 
        s.expect_newline("Syntax error in doc string", ignore_semicolon=True) 
        if kind in ('u', ''): 
            return unicode_result 
        warning(pos, "Python 3 requires docstrings to be unicode strings") 
        return bytes_result 
    else: 
        return None 
 
 
def _extract_docstring(node): 
    """ 
    Extract a docstring from a statement or from the first statement 
    in a list.  Remove the statement if found.  Return a tuple 
    (plain-docstring or None, node). 
    """ 
    doc_node = None 
    if node is None: 
        pass 
    elif isinstance(node, Nodes.ExprStatNode): 
        if node.expr.is_string_literal: 
            doc_node = node.expr 
            node = Nodes.StatListNode(node.pos, stats=[]) 
    elif isinstance(node, Nodes.StatListNode) and node.stats: 
        stats = node.stats 
        if isinstance(stats[0], Nodes.ExprStatNode): 
            if stats[0].expr.is_string_literal: 
                doc_node = stats[0].expr 
                del stats[0] 
 
    if doc_node is None: 
        doc = None 
    elif isinstance(doc_node, ExprNodes.BytesNode): 
        warning(node.pos, 
                "Python 3 requires docstrings to be unicode strings") 
        doc = doc_node.value 
    elif isinstance(doc_node, ExprNodes.StringNode): 
        doc = doc_node.unicode_value 
        if doc is None: 
            doc = doc_node.value 
    else: 
        doc = doc_node.value 
    return doc, node 
 
 
def p_code(s, level=None, ctx=Ctx): 
    body = p_statement_list(s, ctx(level = level), first_statement = 1) 
    if s.sy != 'EOF': 
        s.error("Syntax error in statement [%s,%s]" % ( 
            repr(s.sy), repr(s.systring))) 
    return body 
 

_match_compiler_directive_comment = cython.declare(object, re.compile( 
    r"^#\s*cython\s*:\s*((\w|[.])+\s*=.*)$").match) 
 

def p_compiler_directive_comments(s): 
    result = {} 
    while s.sy == 'commentline': 
        pos = s.position()
        m = _match_compiler_directive_comment(s.systring) 
        if m: 
            directives_string = m.group(1).strip()
            try: 
                new_directives = Options.parse_directive_list(directives_string, ignore_unknown=True)
            except ValueError as e:
                s.error(e.args[0], fatal=False) 
                s.next()
                continue

            for name in new_directives:
                if name not in result:
                    pass
                elif new_directives[name] == result[name]:
                    warning(pos, "Duplicate directive found: %s" % (name,))
                else:
                    s.error("Conflicting settings found for top-level directive %s: %r and %r" % (
                        name, result[name], new_directives[name]), pos=pos)

            if 'language_level' in new_directives:
                # Make sure we apply the language level already to the first token that follows the comments.
                s.context.set_language_level(new_directives['language_level'])

            result.update(new_directives)

        s.next() 
    return result 
 

def p_module(s, pxd, full_module_name, ctx=Ctx): 
    pos = s.position() 
 
    directive_comments = p_compiler_directive_comments(s) 
    s.parse_comments = False 
 
    if s.context.language_level is None:
        s.context.set_language_level(2)  # Arcadia default.
 
    if s.context.language_level is None:
        s.context.set_language_level(2)
        if pos[0].filename:
            import warnings
            warnings.warn(
                "Cython directive 'language_level' not set, using 2 for now (Py2). "
                "This will change in a later release! File: %s" % pos[0].filename,
                FutureWarning,
                stacklevel=1 if cython.compiled else 2,
            )

    doc = p_doc_string(s) 
    if pxd: 
        level = 'module_pxd' 
    else: 
        level = 'module' 
 
    body = p_statement_list(s, ctx(level=level), first_statement = 1) 
    if s.sy != 'EOF': 
        s.error("Syntax error in statement [%s,%s]" % ( 
            repr(s.sy), repr(s.systring))) 
    return ModuleNode(pos, doc = doc, body = body, 
                      full_module_name = full_module_name, 
                      directive_comments = directive_comments) 
 
def p_template_definition(s):
    name = p_ident(s)
    if s.sy == '=':
        s.expect('=')
        s.expect('*')
        required = False
    else:
        required = True
    return name, required

def p_cpp_class_definition(s, pos,  ctx): 
    # s.sy == 'cppclass' 
    s.next() 
    module_path = [] 
    class_name = p_ident(s) 
    cname = p_opt_cname(s) 
    if cname is None and ctx.namespace is not None: 
        cname = ctx.namespace + "::" + class_name 
    if s.sy == '.': 
        error(pos, "Qualified class name not allowed C++ class") 
    if s.sy == '[': 
        s.next() 
        templates = [p_template_definition(s)]
        while s.sy == ',': 
            s.next() 
            templates.append(p_template_definition(s))
        s.expect(']') 
        template_names = [name for name, required in templates]
    else: 
        templates = None 
        template_names = None
    if s.sy == '(': 
        s.next() 
        base_classes = [p_c_base_type(s, templates = template_names)]
        while s.sy == ',': 
            s.next() 
            base_classes.append(p_c_base_type(s, templates = template_names))
        s.expect(')') 
    else: 
        base_classes = [] 
    if s.sy == '[': 
        error(s.position(), "Name options not allowed for C++ class") 
    nogil = p_nogil(s) 
    if s.sy == ':': 
        s.next() 
        s.expect('NEWLINE') 
        s.expect_indent() 
        attributes = [] 
        body_ctx = Ctx(visibility = ctx.visibility, level='cpp_class', nogil=nogil or ctx.nogil) 
        body_ctx.templates = template_names
        while s.sy != 'DEDENT': 
            if s.sy != 'pass': 
                attributes.append(p_cpp_class_attribute(s, body_ctx)) 
            else: 
                s.next() 
                s.expect_newline("Expected a newline") 
        s.expect_dedent() 
    else: 
        attributes = None 
        s.expect_newline("Syntax error in C++ class definition") 
    return Nodes.CppClassNode(pos, 
        name = class_name, 
        cname = cname, 
        base_classes = base_classes, 
        visibility = ctx.visibility, 
        in_pxd = ctx.level == 'module_pxd', 
        attributes = attributes, 
        templates = templates) 
 
def p_cpp_class_attribute(s, ctx): 
    decorators = None 
    if s.sy == '@': 
        decorators = p_decorators(s) 
    if s.systring == 'cppclass': 
        return p_cpp_class_definition(s, s.position(), ctx) 
    elif s.systring == 'ctypedef':
        return p_ctypedef_statement(s, ctx)
    elif s.sy == 'IDENT' and s.systring in struct_enum_union:
        if s.systring != 'enum':
            return p_cpp_class_definition(s, s.position(), ctx)
        else:
            return p_struct_enum(s, s.position(), ctx)
    else: 
        node = p_c_func_or_var_declaration(s, s.position(), ctx) 
        if decorators is not None: 
            tup = Nodes.CFuncDefNode, Nodes.CVarDefNode, Nodes.CClassDefNode 
            if ctx.allow_struct_enum_decorator: 
                tup += Nodes.CStructOrUnionDefNode, Nodes.CEnumDefNode 
            if not isinstance(node, tup): 
                s.error("Decorators can only be followed by functions or classes") 
            node.decorators = decorators 
        return node 
 
 
#---------------------------------------------- 
# 
#   Debugging 
# 
#---------------------------------------------- 
 
def print_parse_tree(f, node, level, key = None): 
    ind = "  " * level 
    if node: 
        f.write(ind) 
        if key: 
            f.write("%s: " % key) 
        t = type(node) 
        if t is tuple: 
            f.write("(%s @ %s\n" % (node[0], node[1])) 
            for i in range(2, len(node)):
                print_parse_tree(f, node[i], level+1) 
            f.write("%s)\n" % ind) 
            return 
        elif isinstance(node, Nodes.Node): 
            try: 
                tag = node.tag 
            except AttributeError: 
                tag = node.__class__.__name__ 
            f.write("%s @ %s\n" % (tag, node.pos)) 
            for name, value in node.__dict__.items(): 
                if name != 'tag' and name != 'pos': 
                    print_parse_tree(f, value, level+1, name) 
            return 
        elif t is list: 
            f.write("[\n") 
            for i in range(len(node)):
                print_parse_tree(f, node[i], level+1) 
            f.write("%s]\n" % ind) 
            return 
    f.write("%s%s\n" % (ind, node))