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# cython: auto_pickle=False 
#=======================================================================
#
#   Python Lexical Analyser
#
#   Actions for use in token specifications
#
#=======================================================================

class Action(object):
    def perform(self, token_stream, text): 
        pass  # abstract 

    def same_as(self, other): 
        return self is other 


class Return(Action):
    """ 
    Internal Plex action which causes |value| to 
    be returned as the value of the associated token 
    """ 

    def __init__(self, value): 
        self.value = value 

    def perform(self, token_stream, text): 
        return self.value 

    def same_as(self, other): 
        return isinstance(other, Return) and self.value == other.value 

    def __repr__(self): 
        return "Return(%s)" % repr(self.value) 


class Call(Action):
    """ 
    Internal Plex action which causes a function to be called. 
    """ 

    def __init__(self, function): 
        self.function = function 

    def perform(self, token_stream, text): 
        return self.function(token_stream, text) 

    def __repr__(self): 
        return "Call(%s)" % self.function.__name__ 

    def same_as(self, other): 
        return isinstance(other, Call) and self.function is other.function 


class Begin(Action):
    """ 
    Begin(state_name) is a Plex action which causes the Scanner to 
    enter the state |state_name|. See the docstring of Plex.Lexicon 
    for more information. 
    """ 

    def __init__(self, state_name): 
        self.state_name = state_name 

    def perform(self, token_stream, text): 
        token_stream.begin(self.state_name) 

    def __repr__(self): 
        return "Begin(%s)" % self.state_name 

    def same_as(self, other): 
        return isinstance(other, Begin) and self.state_name == other.state_name 


class Ignore(Action):
    """ 
    IGNORE is a Plex action which causes its associated token 
    to be ignored. See the docstring of Plex.Lexicon  for more 
    information. 
    """ 

    def perform(self, token_stream, text): 
        return None 

    def __repr__(self): 
        return "IGNORE" 
 
 
IGNORE = Ignore()
#IGNORE.__doc__ = Ignore.__doc__

 
class Text(Action):
    """ 
    TEXT is a Plex action which causes the text of a token to 
    be returned as the value of the token. See the docstring of 
    Plex.Lexicon  for more information. 
    """ 

    def perform(self, token_stream, text): 
        return text 

    def __repr__(self): 
        return "TEXT" 

 
TEXT = Text()
#TEXT.__doc__ = Text.__doc__