aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/tools/cython/Cython/Parser/Grammar
blob: 214e36d5a3f222f708bfed7f11cefbf678912ce2 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
# Grammar for Cython, based on the Grammar for Python 3

# Note: This grammar is not yet used by the Cython parser and is subject to change.

# Start symbols for the grammar:
#       single_input is a single interactive statement;
#       file_input is a module or sequence of commands read from an input file;
#       eval_input is the input for the eval() functions.
# NB: compound_stmt in single_input is followed by extra NEWLINE!
single_input: NEWLINE | simple_stmt | compound_stmt NEWLINE
file_input: (NEWLINE | stmt)* ENDMARKER
eval_input: testlist NEWLINE* ENDMARKER

decorator: '@' dotted_PY_NAME [ '(' [arglist] ')' ] NEWLINE
decorators: decorator+
decorated: decorators (classdef | funcdef | async_funcdef | cdef_stmt)
async_funcdef: 'async' funcdef
funcdef: 'def' PY_NAME parameters ['->' test] ':' suite
parameters: '(' [typedargslist] ')'
typedargslist: (tfpdef ['=' (test | '*')] (',' tfpdef ['=' (test | '*')])* [','
       ['*' [tfpdef] (',' tfpdef ['=' test])* [',' '**' tfpdef] | '**' tfpdef]]
     |  '*' [tfpdef] (',' tfpdef ['=' test])* [',' '**' tfpdef] | '**' tfpdef) [',' ellipsis]
tfpdef: maybe_typed_name [('not' | 'or') 'None'] [':' test]
varargslist: (vfpdef ['=' test] (',' vfpdef ['=' test])* [','
       ['*' [vfpdef] (',' vfpdef ['=' test])* [',' '**' vfpdef] | '**' vfpdef]]
     |  '*' [vfpdef] (',' vfpdef ['=' test])* [',' '**' vfpdef] | '**' vfpdef)
vfpdef: maybe_typed_name ['not' 'None']

stmt: simple_stmt | compound_stmt | cdef_stmt | ctypedef_stmt | DEF_stmt | IF_stmt
simple_stmt: small_stmt (';' small_stmt)* [';'] NEWLINE
small_stmt: (expr_stmt | del_stmt | pass_stmt | flow_stmt |
             import_stmt | global_stmt | nonlocal_stmt | assert_stmt | print_stmt)
expr_stmt: testlist_star_expr (augassign (yield_expr|testlist) |
                     ('=' (yield_expr|testlist_star_expr))*)
testlist_star_expr: (test|star_expr) (',' (test|star_expr))* [',']
augassign: ('+=' | '-=' | '*=' | '/=' | '%=' | '&=' | '|=' | '^=' |
            '<<=' | '>>=' | '**=' | '//=')
print_stmt: 'print' ( [ test (',' test)* [','] ] |
                      '>>' test [ (',' test)+ [','] ] )
# For normal assignments, additional restrictions enforced by the interpreter
del_stmt: 'del' exprlist
pass_stmt: 'pass'
flow_stmt: break_stmt | continue_stmt | return_stmt | raise_stmt | yield_stmt
break_stmt: 'break'
continue_stmt: 'continue'
return_stmt: 'return' [testlist]
yield_stmt: yield_expr
raise_stmt: 'raise' [test ['from' test]]
# raise_stmt: 'raise' [test [',' test [',' test]]]
import_stmt: import_PY_NAME | import_from
import_PY_NAME: ('import' | 'cimport') dotted_as_PY_NAMEs
# note below: the ('.' | '...') is necessary because '...' is tokenized as ELLIPSIS
import_from: ('from' (('.' | '...')* dotted_PY_NAME | ('.' | '...')+)
              ('import' | 'cimport') ('*' | '(' import_as_PY_NAMEs ')' | import_as_PY_NAMEs))
import_as_PY_NAME: PY_NAME ['as' PY_NAME]
dotted_as_PY_NAME: dotted_PY_NAME ['as' PY_NAME]
import_as_PY_NAMEs: import_as_PY_NAME (',' import_as_PY_NAME)* [',']
dotted_as_PY_NAMEs: dotted_as_PY_NAME (',' dotted_as_PY_NAME)*
dotted_PY_NAME: PY_NAME ('.' PY_NAME)*
global_stmt: 'global' PY_NAME (',' PY_NAME)*
nonlocal_stmt: 'nonlocal' PY_NAME (',' PY_NAME)*
exec_stmt: 'exec' expr ['in' test [',' test]]
assert_stmt: 'assert' test [',' test]

compound_stmt: if_stmt | while_stmt | for_stmt | try_stmt | with_stmt | funcdef | classdef | decorated
if_stmt: 'if' test ':' suite ('elif' test ':' suite)* ['else' ':' suite]
while_stmt: 'while' test ':' suite ['else' ':' suite]
for_stmt: 'for' exprlist ('in' testlist | for_from_clause)':' suite ['else' ':' suite]
for_from_clause: 'from' expr comp_op PY_NAME comp_op expr ['by' expr]
try_stmt: ('try' ':' suite
           ((except_clause ':' suite)+
            ['else' ':' suite]
            ['finally' ':' suite] |
           'finally' ':' suite))
with_stmt: 'with' with_item (',' with_item)*  ':' suite
with_item: test ['as' expr]
# NB compile.c makes sure that the default except clause is last
except_clause: 'except' [test [('as' | ',') test]]
suite: simple_stmt | NEWLINE INDENT stmt+ DEDENT

test: or_test ['if' or_test 'else' test] | lambdef
test_nocond: or_test | lambdef_nocond
lambdef: 'lambda' [varargslist] ':' test
lambdef_nocond: 'lambda' [varargslist] ':' test_nocond
or_test: and_test ('or' and_test)*
and_test: not_test ('and' not_test)*
not_test: 'not' not_test | comparison
comparison: expr (comp_op expr)*
# <> isn't actually a valid comparison operator in Python. It's here for the
# sake of a __future__ import described in PEP 401
comp_op: '<'|'>'|'=='|'>='|'<='|'<>'|'!='|'in'|'not' 'in'|'is'|'is' 'not'
star_expr: '*' expr
expr: xor_expr ('|' xor_expr)*
xor_expr: and_expr ('^' and_expr)*
and_expr: shift_expr ('&' shift_expr)*
shift_expr: arith_expr (('<<'|'>>') arith_expr)*
arith_expr: term (('+'|'-') term)*
term: factor (('*'|'/'|'%'|'//') factor)*
factor: ('+'|'-'|'~') factor | power | address | size_of | cast
power: atom_expr ['**' factor]
atom_expr: ['await'] atom trailer*
atom: ('(' [yield_expr|testlist_comp] ')' |
       '[' [testlist_comp] ']' |
       '{' [dictorsetmaker] '}' |
       new_expr |
       PY_NAME | NUMBER | STRING+ | ellipsis | 'None' | 'True' | 'False')
testlist_comp: (test|star_expr) ( comp_for | (',' (test|star_expr))* [','] )
trailer: '(' [arglist] ')' | '[' subscriptlist ']' | '.' (PY_NAME | 'sizeof')
subscriptlist: subscript (',' subscript)* [',']
subscript: test | [test] ':' [test] [sliceop]
sliceop: ':' [test]
exprlist: (expr|star_expr) (',' (expr|star_expr))* [',']
testlist: test (',' test)* [',']
dictorsetmaker: ( ((test ':' test | '**' expr)
                   (comp_for | (',' (test ':' test | '**' expr))* [','])) |
                  ((test | star_expr)
                   (comp_for | (',' (test | star_expr))* [','])) )

classdef: 'class' PY_NAME ['(' [arglist] ')'] ':' suite

arglist: argument (',' argument)*  [',']

# The reason that keywords are test nodes instead of NAME is that using NAME
# results in an ambiguity. ast.c makes sure it's a NAME.
# "test '=' test" is really "keyword '=' test", but we have no such token.
# These need to be in a single rule to avoid grammar that is ambiguous
# to our LL(1) parser. Even though 'test' includes '*expr' in star_expr,
# we explicitly match '*' here, too, to give it proper precedence.
# Illegal combinations and orderings are blocked in ast.c:
# multiple (test comp_for) arguments are blocked; keyword unpackings
# that precede iterable unpackings are blocked; etc.
argument: ( test [comp_for] |
            test '=' test |
            '**' expr |
            star_expr )

comp_iter: comp_for | comp_if
comp_for: 'for' exprlist ('in' or_test | for_from_clause) [comp_iter]
comp_if: 'if' test_nocond [comp_iter]

# not used in grammar, but may appear in "node" passed from Parser to Compiler
encoding_decl: NAME

yield_expr: 'yield' [yield_arg]
yield_arg: 'from' test | testlist


# Cython extensions

# Accommodate to Py2 tokenizer.
ellipsis: '...' | '.' '.' '.'

signedness: 'unsigned' | 'signed'
longness: 'char' | 'short' | 'long' | 'long' 'long'
# TODO: [unsigned] double doesn't make sens, but we need long double
int_type: signedness [longness] | longness | [signedness] [longness] ('int' | 'double')  | 'complex'

type: ['const'] (NAME ('.' PY_NAME)* | int_type | '(' type ')') ['complex'] [type_qualifiers]
maybe_typed_name: ['const'] (NAME [('.' PY_NAME)* ['complex'] [type_qualifiers] NAME] | (int_type | '(' type ')') ['complex'] [type_qualifiers] NAME)
teplate_params: '[' NAME (',' NAME)* ']'
type_qualifiers: type_qualifier+
type_qualifier: '*' | '**' | '&' | type_index ('.' NAME [type_index])*
# TODO: old buffer syntax
type_index: '[' [(NUMBER | type (',' type)* | (memory_view_index (',' memory_view_index)*))] ']'
memory_view_index: ':' [':'] [NUMBER]

address: '&' factor
cast: '<' type ['?'] '>' factor
size_of: 'sizeof' '(' (type) ')'
type_id: 'typeid' '(' (type) ')'
new_expr: 'new' type '(' [arglist] ')'

# TODO: Restrict cdef_stmt to "top-level" statements.
cdef_stmt: ('cdef' | 'cpdef') (cvar_def | cdef_type_decl | extern_block)
cdef_type_decl: ctype_decl | fused | cclass
ctype_decl: struct | enum | cppclass
# TODO: Does the cdef/ctypedef distinction even make sense for fused?
ctypedef_stmt: 'ctypedef' (cvar_decl | struct | enum | fused)

# Note: these two are similar but can't be used in an or clause
# as it would cause ambiguity in the LL(1) parser.
# Requires a type
cvar_decl: [visibility] type cname (NEWLINE | cfunc)
# Allows an assignment
cvar_def: [visibility] maybe_typed_name (['=' test] (',' PY_NAME ['=' test])* NEWLINE | cfunc)

visibility: 'public' | 'api' | 'readonly'
# TODO: Standardize gil_spec first or last.
cfunc: [teplate_params] parameters [gil_spec] [exception_value] [gil_spec] (':' suite | NEWLINE)
exception_value: 'except' (['?'] expr | '*' | '+' [PY_NAME])
gil_spec: 'with' ('gil' | 'nogil') | 'nogil'

cname: NAME [STRING]
cclass: classdef
fused: 'fused' PY_NAME ':' NEWLINE INDENT ( type NEWLINE)+ DEDENT
enum: 'enum' [cname] (NEWLINE | ':' enum_suite)
enum_suite: NEWLINE INDENT (cname ['=' NUMBER] NEWLINE | pass_stmt NEWLINE)+ DEDENT
struct: ('struct' | 'union') cname (NEWLINE | (':' struct_suite))
struct_suite: NEWLINE INDENT (cvar_decl | pass_stmt NEWLINE)+ DEDENT
cppclass: 'cppclass' cname [teplate_params] [cppclass_bases] (NEWLINE | ':' cppclass_suite)
cppclass_bases: '(' dotted_PY_NAME (',' dotted_PY_NAME [teplate_params])*')'
cppclass_suite: NEWLINE INDENT (cvar_decl | ctype_decl | pass_stmt NEWLINE)+ DEDENT
# TODO: C++ constructors, operators

extern_block: 'extern' (cvar_decl | 'from' ('*' | STRING) ['namespace' STRING] [gil_spec] ':' (pass_stmt | extern_suite))
extern_suite: NEWLINE INDENT (['cdef' | 'cpdef'] (cvar_decl | cdef_type_decl) | ctypedef_stmt)+ DEDENT

cy_type_kwd: 'struct' | 'union' | 'fused' | 'cppclass' | 'int' | 'double' | 'complex'
cy_kwd: cy_type_kwd | signedness | longness | visibility | 'gil' | 'nogil' | 'namespace' | 'const' | 'by' | 'extern'
PY_NAME: NAME | cy_kwd

# TODO: Do we really want these? Don't play well with include...
DEF_stmt: 'DEF' NAME '=' testlist
IF_stmt: 'IF' test ':' suite ('ELIF' test ':' suite)* ['ELSE' ':' suite]