1059 lines
40 KiB
Python
1059 lines
40 KiB
Python
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# -----------------------------------------------------------------------------
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# ply: lex.py
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#
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# Copyright (C) 2001-2009,
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# David M. Beazley (Dabeaz LLC)
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# All rights reserved.
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#
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# Redistribution and use in source and binary forms, with or without
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# modification, are permitted provided that the following conditions are
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# met:
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#
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# * Redistributions of source code must retain the above copyright notice,
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# this list of conditions and the following disclaimer.
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# * Redistributions in binary form must reproduce the above copyright notice,
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# this list of conditions and the following disclaimer in the documentation
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# and/or other materials provided with the distribution.
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# * Neither the name of the David Beazley or Dabeaz LLC may be used to
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# endorse or promote products derived from this software without
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# specific prior written permission.
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#
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# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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# -----------------------------------------------------------------------------
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__version__ = "3.3"
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__tabversion__ = "3.2" # Version of table file used
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import re, sys, types, copy, os
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# This tuple contains known string types
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try:
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# Python 2.6
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StringTypes = (types.StringType, types.UnicodeType)
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except AttributeError:
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# Python 3.0
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StringTypes = (str, bytes)
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# Extract the code attribute of a function. Different implementations
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# are for Python 2/3 compatibility.
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if sys.version_info[0] < 3:
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def func_code(f):
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return f.func_code
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else:
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def func_code(f):
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return f.__code__
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# This regular expression is used to match valid token names
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_is_identifier = re.compile(r'^[a-zA-Z0-9_]+$')
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# Exception thrown when invalid token encountered and no default error
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# handler is defined.
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class LexError(Exception):
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def __init__(self,message,s):
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self.args = (message,)
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self.text = s
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# Token class. This class is used to represent the tokens produced.
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class LexToken(object):
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def __str__(self):
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return "LexToken(%s,%r,%d,%d)" % (self.type,self.value,self.lineno,self.lexpos)
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def __repr__(self):
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return str(self)
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# This object is a stand-in for a logging object created by the
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# logging module.
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class PlyLogger(object):
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def __init__(self,f):
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self.f = f
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def critical(self,msg,*args,**kwargs):
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self.f.write((msg % args) + "\n")
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def warning(self,msg,*args,**kwargs):
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self.f.write("WARNING: "+ (msg % args) + "\n")
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def error(self,msg,*args,**kwargs):
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self.f.write("ERROR: " + (msg % args) + "\n")
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info = critical
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debug = critical
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# Null logger is used when no output is generated. Does nothing.
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class NullLogger(object):
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def __getattribute__(self,name):
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return self
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def __call__(self,*args,**kwargs):
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return self
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# -----------------------------------------------------------------------------
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# === Lexing Engine ===
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#
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# The following Lexer class implements the lexer runtime. There are only
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# a few public methods and attributes:
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#
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# input() - Store a new string in the lexer
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# token() - Get the next token
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# clone() - Clone the lexer
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#
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# lineno - Current line number
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# lexpos - Current position in the input string
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# -----------------------------------------------------------------------------
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class Lexer:
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def __init__(self):
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self.lexre = None # Master regular expression. This is a list of
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# tuples (re,findex) where re is a compiled
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# regular expression and findex is a list
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# mapping regex group numbers to rules
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self.lexretext = None # Current regular expression strings
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self.lexstatere = {} # Dictionary mapping lexer states to master regexs
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self.lexstateretext = {} # Dictionary mapping lexer states to regex strings
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self.lexstaterenames = {} # Dictionary mapping lexer states to symbol names
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self.lexstate = "INITIAL" # Current lexer state
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self.lexstatestack = [] # Stack of lexer states
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self.lexstateinfo = None # State information
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self.lexstateignore = {} # Dictionary of ignored characters for each state
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self.lexstateerrorf = {} # Dictionary of error functions for each state
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self.lexreflags = 0 # Optional re compile flags
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self.lexdata = None # Actual input data (as a string)
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self.lexpos = 0 # Current position in input text
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self.lexlen = 0 # Length of the input text
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self.lexerrorf = None # Error rule (if any)
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self.lextokens = None # List of valid tokens
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self.lexignore = "" # Ignored characters
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self.lexliterals = "" # Literal characters that can be passed through
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self.lexmodule = None # Module
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self.lineno = 1 # Current line number
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self.lexoptimize = 0 # Optimized mode
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def clone(self,object=None):
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c = copy.copy(self)
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# If the object parameter has been supplied, it means we are attaching the
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# lexer to a new object. In this case, we have to rebind all methods in
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# the lexstatere and lexstateerrorf tables.
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if object:
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newtab = { }
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for key, ritem in self.lexstatere.items():
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newre = []
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for cre, findex in ritem:
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newfindex = []
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for f in findex:
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if not f or not f[0]:
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newfindex.append(f)
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continue
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newfindex.append((getattr(object,f[0].__name__),f[1]))
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newre.append((cre,newfindex))
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newtab[key] = newre
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c.lexstatere = newtab
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c.lexstateerrorf = { }
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for key, ef in self.lexstateerrorf.items():
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c.lexstateerrorf[key] = getattr(object,ef.__name__)
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c.lexmodule = object
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return c
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# ------------------------------------------------------------
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# writetab() - Write lexer information to a table file
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# ------------------------------------------------------------
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def writetab(self,tabfile,outputdir=""):
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if isinstance(tabfile,types.ModuleType):
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return
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basetabfilename = tabfile.split(".")[-1]
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filename = os.path.join(outputdir,basetabfilename)+".py"
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tf = open(filename,"w")
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tf.write("# %s.py. This file automatically created by PLY (version %s). Don't edit!\n" % (tabfile,__version__))
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tf.write("_tabversion = %s\n" % repr(__version__))
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tf.write("_lextokens = %s\n" % repr(self.lextokens))
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tf.write("_lexreflags = %s\n" % repr(self.lexreflags))
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tf.write("_lexliterals = %s\n" % repr(self.lexliterals))
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tf.write("_lexstateinfo = %s\n" % repr(self.lexstateinfo))
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tabre = { }
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# Collect all functions in the initial state
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initial = self.lexstatere["INITIAL"]
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initialfuncs = []
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for part in initial:
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for f in part[1]:
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if f and f[0]:
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initialfuncs.append(f)
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for key, lre in self.lexstatere.items():
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titem = []
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for i in range(len(lre)):
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titem.append((self.lexstateretext[key][i],_funcs_to_names(lre[i][1],self.lexstaterenames[key][i])))
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tabre[key] = titem
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tf.write("_lexstatere = %s\n" % repr(tabre))
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tf.write("_lexstateignore = %s\n" % repr(self.lexstateignore))
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taberr = { }
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for key, ef in self.lexstateerrorf.items():
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if ef:
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taberr[key] = ef.__name__
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else:
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taberr[key] = None
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tf.write("_lexstateerrorf = %s\n" % repr(taberr))
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tf.close()
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# ------------------------------------------------------------
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# readtab() - Read lexer information from a tab file
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# ------------------------------------------------------------
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def readtab(self,tabfile,fdict):
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if isinstance(tabfile,types.ModuleType):
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lextab = tabfile
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else:
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if sys.version_info[0] < 3:
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exec("import %s as lextab" % tabfile)
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else:
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env = { }
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exec("import %s as lextab" % tabfile, env,env)
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lextab = env['lextab']
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if getattr(lextab,"_tabversion","0.0") != __version__:
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raise ImportError("Inconsistent PLY version")
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self.lextokens = lextab._lextokens
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self.lexreflags = lextab._lexreflags
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self.lexliterals = lextab._lexliterals
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self.lexstateinfo = lextab._lexstateinfo
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self.lexstateignore = lextab._lexstateignore
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self.lexstatere = { }
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self.lexstateretext = { }
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for key,lre in lextab._lexstatere.items():
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titem = []
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txtitem = []
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for i in range(len(lre)):
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titem.append((re.compile(lre[i][0],lextab._lexreflags | re.VERBOSE),_names_to_funcs(lre[i][1],fdict)))
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txtitem.append(lre[i][0])
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self.lexstatere[key] = titem
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self.lexstateretext[key] = txtitem
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self.lexstateerrorf = { }
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for key,ef in lextab._lexstateerrorf.items():
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self.lexstateerrorf[key] = fdict[ef]
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self.begin('INITIAL')
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# ------------------------------------------------------------
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# input() - Push a new string into the lexer
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# ------------------------------------------------------------
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def input(self,s):
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# Pull off the first character to see if s looks like a string
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c = s[:1]
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if not isinstance(c,StringTypes):
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raise ValueError("Expected a string")
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self.lexdata = s
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self.lexpos = 0
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self.lexlen = len(s)
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# ------------------------------------------------------------
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# begin() - Changes the lexing state
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# ------------------------------------------------------------
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def begin(self,state):
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if not state in self.lexstatere:
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raise ValueError("Undefined state")
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self.lexre = self.lexstatere[state]
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self.lexretext = self.lexstateretext[state]
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self.lexignore = self.lexstateignore.get(state,"")
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self.lexerrorf = self.lexstateerrorf.get(state,None)
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self.lexstate = state
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# ------------------------------------------------------------
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# push_state() - Changes the lexing state and saves old on stack
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# ------------------------------------------------------------
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def push_state(self,state):
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self.lexstatestack.append(self.lexstate)
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self.begin(state)
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# ------------------------------------------------------------
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# pop_state() - Restores the previous state
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# ------------------------------------------------------------
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def pop_state(self):
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self.begin(self.lexstatestack.pop())
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# ------------------------------------------------------------
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# current_state() - Returns the current lexing state
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# ------------------------------------------------------------
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def current_state(self):
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return self.lexstate
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# ------------------------------------------------------------
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# skip() - Skip ahead n characters
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# ------------------------------------------------------------
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def skip(self,n):
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self.lexpos += n
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# ------------------------------------------------------------
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# opttoken() - Return the next token from the Lexer
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#
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# Note: This function has been carefully implemented to be as fast
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# as possible. Don't make changes unless you really know what
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# you are doing
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# ------------------------------------------------------------
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def token(self):
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# Make local copies of frequently referenced attributes
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lexpos = self.lexpos
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lexlen = self.lexlen
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lexignore = self.lexignore
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lexdata = self.lexdata
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while lexpos < lexlen:
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# This code provides some short-circuit code for whitespace, tabs, and other ignored characters
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if lexdata[lexpos] in lexignore:
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lexpos += 1
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continue
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# Look for a regular expression match
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for lexre,lexindexfunc in self.lexre:
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m = lexre.match(lexdata,lexpos)
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if not m: continue
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# Create a token for return
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tok = LexToken()
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tok.value = m.group()
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tok.lineno = self.lineno
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tok.lexpos = lexpos
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i = m.lastindex
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func,tok.type = lexindexfunc[i]
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if not func:
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# If no token type was set, it's an ignored token
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if tok.type:
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self.lexpos = m.end()
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return tok
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else:
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lexpos = m.end()
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break
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lexpos = m.end()
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# If token is processed by a function, call it
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tok.lexer = self # Set additional attributes useful in token rules
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self.lexmatch = m
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self.lexpos = lexpos
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newtok = func(tok)
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# Every function must return a token, if nothing, we just move to next token
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if not newtok:
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lexpos = self.lexpos # This is here in case user has updated lexpos.
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lexignore = self.lexignore # This is here in case there was a state change
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break
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# Verify type of the token. If not in the token map, raise an error
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if not self.lexoptimize:
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if not newtok.type in self.lextokens:
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raise LexError("%s:%d: Rule '%s' returned an unknown token type '%s'" % (
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func_code(func).co_filename, func_code(func).co_firstlineno,
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func.__name__, newtok.type),lexdata[lexpos:])
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return newtok
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else:
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# No match, see if in literals
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if lexdata[lexpos] in self.lexliterals:
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tok = LexToken()
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tok.value = lexdata[lexpos]
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tok.lineno = self.lineno
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tok.type = tok.value
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tok.lexpos = lexpos
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self.lexpos = lexpos + 1
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return tok
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# No match. Call t_error() if defined.
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if self.lexerrorf:
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tok = LexToken()
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tok.value = self.lexdata[lexpos:]
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tok.lineno = self.lineno
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tok.type = "error"
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tok.lexer = self
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tok.lexpos = lexpos
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self.lexpos = lexpos
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newtok = self.lexerrorf(tok)
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if lexpos == self.lexpos:
|
||
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# Error method didn't change text position at all. This is an error.
|
||
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raise LexError("Scanning error. Illegal character '%s'" % (lexdata[lexpos]), lexdata[lexpos:])
|
||
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lexpos = self.lexpos
|
||
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if not newtok: continue
|
||
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return newtok
|
||
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|
||
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self.lexpos = lexpos
|
||
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raise LexError("Illegal character '%s' at index %d" % (lexdata[lexpos],lexpos), lexdata[lexpos:])
|
||
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||
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self.lexpos = lexpos + 1
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if self.lexdata is None:
|
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raise RuntimeError("No input string given with input()")
|
||
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return None
|
||
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|
||
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# Iterator interface
|
||
|
def __iter__(self):
|
||
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return self
|
||
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|
||
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def next(self):
|
||
|
t = self.token()
|
||
|
if t is None:
|
||
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raise StopIteration
|
||
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return t
|
||
|
|
||
|
__next__ = next
|
||
|
|
||
|
# -----------------------------------------------------------------------------
|
||
|
# ==== Lex Builder ===
|
||
|
#
|
||
|
# The functions and classes below are used to collect lexing information
|
||
|
# and build a Lexer object from it.
|
||
|
# -----------------------------------------------------------------------------
|
||
|
|
||
|
# -----------------------------------------------------------------------------
|
||
|
# get_caller_module_dict()
|
||
|
#
|
||
|
# This function returns a dictionary containing all of the symbols defined within
|
||
|
# a caller further down the call stack. This is used to get the environment
|
||
|
# associated with the yacc() call if none was provided.
|
||
|
# -----------------------------------------------------------------------------
|
||
|
|
||
|
def get_caller_module_dict(levels):
|
||
|
try:
|
||
|
raise RuntimeError
|
||
|
except RuntimeError:
|
||
|
e,b,t = sys.exc_info()
|
||
|
f = t.tb_frame
|
||
|
while levels > 0:
|
||
|
f = f.f_back
|
||
|
levels -= 1
|
||
|
ldict = f.f_globals.copy()
|
||
|
if f.f_globals != f.f_locals:
|
||
|
ldict.update(f.f_locals)
|
||
|
|
||
|
return ldict
|
||
|
|
||
|
# -----------------------------------------------------------------------------
|
||
|
# _funcs_to_names()
|
||
|
#
|
||
|
# Given a list of regular expression functions, this converts it to a list
|
||
|
# suitable for output to a table file
|
||
|
# -----------------------------------------------------------------------------
|
||
|
|
||
|
def _funcs_to_names(funclist,namelist):
|
||
|
result = []
|
||
|
for f,name in zip(funclist,namelist):
|
||
|
if f and f[0]:
|
||
|
result.append((name, f[1]))
|
||
|
else:
|
||
|
result.append(f)
|
||
|
return result
|
||
|
|
||
|
# -----------------------------------------------------------------------------
|
||
|
# _names_to_funcs()
|
||
|
#
|
||
|
# Given a list of regular expression function names, this converts it back to
|
||
|
# functions.
|
||
|
# -----------------------------------------------------------------------------
|
||
|
|
||
|
def _names_to_funcs(namelist,fdict):
|
||
|
result = []
|
||
|
for n in namelist:
|
||
|
if n and n[0]:
|
||
|
result.append((fdict[n[0]],n[1]))
|
||
|
else:
|
||
|
result.append(n)
|
||
|
return result
|
||
|
|
||
|
# -----------------------------------------------------------------------------
|
||
|
# _form_master_re()
|
||
|
#
|
||
|
# This function takes a list of all of the regex components and attempts to
|
||
|
# form the master regular expression. Given limitations in the Python re
|
||
|
# module, it may be necessary to break the master regex into separate expressions.
|
||
|
# -----------------------------------------------------------------------------
|
||
|
|
||
|
def _form_master_re(relist,reflags,ldict,toknames):
|
||
|
if not relist: return []
|
||
|
regex = "|".join(relist)
|
||
|
try:
|
||
|
lexre = re.compile(regex,re.VERBOSE | reflags)
|
||
|
|
||
|
# Build the index to function map for the matching engine
|
||
|
lexindexfunc = [ None ] * (max(lexre.groupindex.values())+1)
|
||
|
lexindexnames = lexindexfunc[:]
|
||
|
|
||
|
for f,i in lexre.groupindex.items():
|
||
|
handle = ldict.get(f,None)
|
||
|
if type(handle) in (types.FunctionType, types.MethodType):
|
||
|
lexindexfunc[i] = (handle,toknames[f])
|
||
|
lexindexnames[i] = f
|
||
|
elif handle is not None:
|
||
|
lexindexnames[i] = f
|
||
|
if f.find("ignore_") > 0:
|
||
|
lexindexfunc[i] = (None,None)
|
||
|
else:
|
||
|
lexindexfunc[i] = (None, toknames[f])
|
||
|
|
||
|
return [(lexre,lexindexfunc)],[regex],[lexindexnames]
|
||
|
except Exception:
|
||
|
m = int(len(relist)/2)
|
||
|
if m == 0: m = 1
|
||
|
llist, lre, lnames = _form_master_re(relist[:m],reflags,ldict,toknames)
|
||
|
rlist, rre, rnames = _form_master_re(relist[m:],reflags,ldict,toknames)
|
||
|
return llist+rlist, lre+rre, lnames+rnames
|
||
|
|
||
|
# -----------------------------------------------------------------------------
|
||
|
# def _statetoken(s,names)
|
||
|
#
|
||
|
# Given a declaration name s of the form "t_" and a dictionary whose keys are
|
||
|
# state names, this function returns a tuple (states,tokenname) where states
|
||
|
# is a tuple of state names and tokenname is the name of the token. For example,
|
||
|
# calling this with s = "t_foo_bar_SPAM" might return (('foo','bar'),'SPAM')
|
||
|
# -----------------------------------------------------------------------------
|
||
|
|
||
|
def _statetoken(s,names):
|
||
|
nonstate = 1
|
||
|
parts = s.split("_")
|
||
|
for i in range(1,len(parts)):
|
||
|
if not parts[i] in names and parts[i] != 'ANY': break
|
||
|
if i > 1:
|
||
|
states = tuple(parts[1:i])
|
||
|
else:
|
||
|
states = ('INITIAL',)
|
||
|
|
||
|
if 'ANY' in states:
|
||
|
states = tuple(names)
|
||
|
|
||
|
tokenname = "_".join(parts[i:])
|
||
|
return (states,tokenname)
|
||
|
|
||
|
|
||
|
# -----------------------------------------------------------------------------
|
||
|
# LexerReflect()
|
||
|
#
|
||
|
# This class represents information needed to build a lexer as extracted from a
|
||
|
# user's input file.
|
||
|
# -----------------------------------------------------------------------------
|
||
|
class LexerReflect(object):
|
||
|
def __init__(self,ldict,log=None,reflags=0):
|
||
|
self.ldict = ldict
|
||
|
self.error_func = None
|
||
|
self.tokens = []
|
||
|
self.reflags = reflags
|
||
|
self.stateinfo = { 'INITIAL' : 'inclusive'}
|
||
|
self.files = {}
|
||
|
self.error = 0
|
||
|
|
||
|
if log is None:
|
||
|
self.log = PlyLogger(sys.stderr)
|
||
|
else:
|
||
|
self.log = log
|
||
|
|
||
|
# Get all of the basic information
|
||
|
def get_all(self):
|
||
|
self.get_tokens()
|
||
|
self.get_literals()
|
||
|
self.get_states()
|
||
|
self.get_rules()
|
||
|
|
||
|
# Validate all of the information
|
||
|
def validate_all(self):
|
||
|
self.validate_tokens()
|
||
|
self.validate_literals()
|
||
|
self.validate_rules()
|
||
|
return self.error
|
||
|
|
||
|
# Get the tokens map
|
||
|
def get_tokens(self):
|
||
|
tokens = self.ldict.get("tokens",None)
|
||
|
if not tokens:
|
||
|
self.log.error("No token list is defined")
|
||
|
self.error = 1
|
||
|
return
|
||
|
|
||
|
if not isinstance(tokens,(list, tuple)):
|
||
|
self.log.error("tokens must be a list or tuple")
|
||
|
self.error = 1
|
||
|
return
|
||
|
|
||
|
if not tokens:
|
||
|
self.log.error("tokens is empty")
|
||
|
self.error = 1
|
||
|
return
|
||
|
|
||
|
self.tokens = tokens
|
||
|
|
||
|
# Validate the tokens
|
||
|
def validate_tokens(self):
|
||
|
terminals = {}
|
||
|
for n in self.tokens:
|
||
|
if not _is_identifier.match(n):
|
||
|
self.log.error("Bad token name '%s'",n)
|
||
|
self.error = 1
|
||
|
if n in terminals:
|
||
|
self.log.warning("Token '%s' multiply defined", n)
|
||
|
terminals[n] = 1
|
||
|
|
||
|
# Get the literals specifier
|
||
|
def get_literals(self):
|
||
|
self.literals = self.ldict.get("literals","")
|
||
|
|
||
|
# Validate literals
|
||
|
def validate_literals(self):
|
||
|
try:
|
||
|
for c in self.literals:
|
||
|
if not isinstance(c,StringTypes) or len(c) > 1:
|
||
|
self.log.error("Invalid literal %s. Must be a single character", repr(c))
|
||
|
self.error = 1
|
||
|
continue
|
||
|
|
||
|
except TypeError:
|
||
|
self.log.error("Invalid literals specification. literals must be a sequence of characters")
|
||
|
self.error = 1
|
||
|
|
||
|
def get_states(self):
|
||
|
self.states = self.ldict.get("states",None)
|
||
|
# Build statemap
|
||
|
if self.states:
|
||
|
if not isinstance(self.states,(tuple,list)):
|
||
|
self.log.error("states must be defined as a tuple or list")
|
||
|
self.error = 1
|
||
|
else:
|
||
|
for s in self.states:
|
||
|
if not isinstance(s,tuple) or len(s) != 2:
|
||
|
self.log.error("Invalid state specifier %s. Must be a tuple (statename,'exclusive|inclusive')",repr(s))
|
||
|
self.error = 1
|
||
|
continue
|
||
|
name, statetype = s
|
||
|
if not isinstance(name,StringTypes):
|
||
|
self.log.error("State name %s must be a string", repr(name))
|
||
|
self.error = 1
|
||
|
continue
|
||
|
if not (statetype == 'inclusive' or statetype == 'exclusive'):
|
||
|
self.log.error("State type for state %s must be 'inclusive' or 'exclusive'",name)
|
||
|
self.error = 1
|
||
|
continue
|
||
|
if name in self.stateinfo:
|
||
|
self.log.error("State '%s' already defined",name)
|
||
|
self.error = 1
|
||
|
continue
|
||
|
self.stateinfo[name] = statetype
|
||
|
|
||
|
# Get all of the symbols with a t_ prefix and sort them into various
|
||
|
# categories (functions, strings, error functions, and ignore characters)
|
||
|
|
||
|
def get_rules(self):
|
||
|
tsymbols = [f for f in self.ldict if f[:2] == 't_' ]
|
||
|
|
||
|
# Now build up a list of functions and a list of strings
|
||
|
|
||
|
self.toknames = { } # Mapping of symbols to token names
|
||
|
self.funcsym = { } # Symbols defined as functions
|
||
|
self.strsym = { } # Symbols defined as strings
|
||
|
self.ignore = { } # Ignore strings by state
|
||
|
self.errorf = { } # Error functions by state
|
||
|
|
||
|
for s in self.stateinfo:
|
||
|
self.funcsym[s] = []
|
||
|
self.strsym[s] = []
|
||
|
|
||
|
if len(tsymbols) == 0:
|
||
|
self.log.error("No rules of the form t_rulename are defined")
|
||
|
self.error = 1
|
||
|
return
|
||
|
|
||
|
for f in tsymbols:
|
||
|
t = self.ldict[f]
|
||
|
states, tokname = _statetoken(f,self.stateinfo)
|
||
|
self.toknames[f] = tokname
|
||
|
|
||
|
if hasattr(t,"__call__"):
|
||
|
if tokname == 'error':
|
||
|
for s in states:
|
||
|
self.errorf[s] = t
|
||
|
elif tokname == 'ignore':
|
||
|
line = func_code(t).co_firstlineno
|
||
|
file = func_code(t).co_filename
|
||
|
self.log.error("%s:%d: Rule '%s' must be defined as a string",file,line,t.__name__)
|
||
|
self.error = 1
|
||
|
else:
|
||
|
for s in states:
|
||
|
self.funcsym[s].append((f,t))
|
||
|
elif isinstance(t, StringTypes):
|
||
|
if tokname == 'ignore':
|
||
|
for s in states:
|
||
|
self.ignore[s] = t
|
||
|
if "\\" in t:
|
||
|
self.log.warning("%s contains a literal backslash '\\'",f)
|
||
|
|
||
|
elif tokname == 'error':
|
||
|
self.log.error("Rule '%s' must be defined as a function", f)
|
||
|
self.error = 1
|
||
|
else:
|
||
|
for s in states:
|
||
|
self.strsym[s].append((f,t))
|
||
|
else:
|
||
|
self.log.error("%s not defined as a function or string", f)
|
||
|
self.error = 1
|
||
|
|
||
|
# Sort the functions by line number
|
||
|
for f in self.funcsym.values():
|
||
|
if sys.version_info[0] < 3:
|
||
|
f.sort(lambda x,y: cmp(func_code(x[1]).co_firstlineno,func_code(y[1]).co_firstlineno))
|
||
|
else:
|
||
|
# Python 3.0
|
||
|
f.sort(key=lambda x: func_code(x[1]).co_firstlineno)
|
||
|
|
||
|
# Sort the strings by regular expression length
|
||
|
for s in self.strsym.values():
|
||
|
if sys.version_info[0] < 3:
|
||
|
s.sort(lambda x,y: (len(x[1]) < len(y[1])) - (len(x[1]) > len(y[1])))
|
||
|
else:
|
||
|
# Python 3.0
|
||
|
s.sort(key=lambda x: len(x[1]),reverse=True)
|
||
|
|
||
|
# Validate all of the t_rules collected
|
||
|
def validate_rules(self):
|
||
|
for state in self.stateinfo:
|
||
|
# Validate all rules defined by functions
|
||
|
|
||
|
|
||
|
|
||
|
for fname, f in self.funcsym[state]:
|
||
|
line = func_code(f).co_firstlineno
|
||
|
file = func_code(f).co_filename
|
||
|
self.files[file] = 1
|
||
|
|
||
|
tokname = self.toknames[fname]
|
||
|
if isinstance(f, types.MethodType):
|
||
|
reqargs = 2
|
||
|
else:
|
||
|
reqargs = 1
|
||
|
nargs = func_code(f).co_argcount
|
||
|
if nargs > reqargs:
|
||
|
self.log.error("%s:%d: Rule '%s' has too many arguments",file,line,f.__name__)
|
||
|
self.error = 1
|
||
|
continue
|
||
|
|
||
|
if nargs < reqargs:
|
||
|
self.log.error("%s:%d: Rule '%s' requires an argument", file,line,f.__name__)
|
||
|
self.error = 1
|
||
|
continue
|
||
|
|
||
|
if not f.__doc__:
|
||
|
self.log.error("%s:%d: No regular expression defined for rule '%s'",file,line,f.__name__)
|
||
|
self.error = 1
|
||
|
continue
|
||
|
|
||
|
try:
|
||
|
c = re.compile("(?P<%s>%s)" % (fname,f.__doc__), re.VERBOSE | self.reflags)
|
||
|
if c.match(""):
|
||
|
self.log.error("%s:%d: Regular expression for rule '%s' matches empty string", file,line,f.__name__)
|
||
|
self.error = 1
|
||
|
except re.error:
|
||
|
_etype, e, _etrace = sys.exc_info()
|
||
|
self.log.error("%s:%d: Invalid regular expression for rule '%s'. %s", file,line,f.__name__,e)
|
||
|
if '#' in f.__doc__:
|
||
|
self.log.error("%s:%d. Make sure '#' in rule '%s' is escaped with '\\#'",file,line, f.__name__)
|
||
|
self.error = 1
|
||
|
|
||
|
# Validate all rules defined by strings
|
||
|
for name,r in self.strsym[state]:
|
||
|
tokname = self.toknames[name]
|
||
|
if tokname == 'error':
|
||
|
self.log.error("Rule '%s' must be defined as a function", name)
|
||
|
self.error = 1
|
||
|
continue
|
||
|
|
||
|
if not tokname in self.tokens and tokname.find("ignore_") < 0:
|
||
|
self.log.error("Rule '%s' defined for an unspecified token %s",name,tokname)
|
||
|
self.error = 1
|
||
|
continue
|
||
|
|
||
|
try:
|
||
|
c = re.compile("(?P<%s>%s)" % (name,r),re.VERBOSE | self.reflags)
|
||
|
if (c.match("")):
|
||
|
self.log.error("Regular expression for rule '%s' matches empty string",name)
|
||
|
self.error = 1
|
||
|
except re.error:
|
||
|
_etype, e, _etrace = sys.exc_info()
|
||
|
self.log.error("Invalid regular expression for rule '%s'. %s",name,e)
|
||
|
if '#' in r:
|
||
|
self.log.error("Make sure '#' in rule '%s' is escaped with '\\#'",name)
|
||
|
self.error = 1
|
||
|
|
||
|
if not self.funcsym[state] and not self.strsym[state]:
|
||
|
self.log.error("No rules defined for state '%s'",state)
|
||
|
self.error = 1
|
||
|
|
||
|
# Validate the error function
|
||
|
efunc = self.errorf.get(state,None)
|
||
|
if efunc:
|
||
|
f = efunc
|
||
|
line = func_code(f).co_firstlineno
|
||
|
file = func_code(f).co_filename
|
||
|
self.files[file] = 1
|
||
|
|
||
|
if isinstance(f, types.MethodType):
|
||
|
reqargs = 2
|
||
|
else:
|
||
|
reqargs = 1
|
||
|
nargs = func_code(f).co_argcount
|
||
|
if nargs > reqargs:
|
||
|
self.log.error("%s:%d: Rule '%s' has too many arguments",file,line,f.__name__)
|
||
|
self.error = 1
|
||
|
|
||
|
if nargs < reqargs:
|
||
|
self.log.error("%s:%d: Rule '%s' requires an argument", file,line,f.__name__)
|
||
|
self.error = 1
|
||
|
|
||
|
for f in self.files:
|
||
|
self.validate_file(f)
|
||
|
|
||
|
|
||
|
# -----------------------------------------------------------------------------
|
||
|
# validate_file()
|
||
|
#
|
||
|
# This checks to see if there are duplicated t_rulename() functions or strings
|
||
|
# in the parser input file. This is done using a simple regular expression
|
||
|
# match on each line in the given file.
|
||
|
# -----------------------------------------------------------------------------
|
||
|
|
||
|
def validate_file(self,filename):
|
||
|
import os.path
|
||
|
base,ext = os.path.splitext(filename)
|
||
|
if ext != '.py': return # No idea what the file is. Return OK
|
||
|
|
||
|
try:
|
||
|
f = open(filename)
|
||
|
lines = f.readlines()
|
||
|
f.close()
|
||
|
except IOError:
|
||
|
return # Couldn't find the file. Don't worry about it
|
||
|
|
||
|
fre = re.compile(r'\s*def\s+(t_[a-zA-Z_0-9]*)\(')
|
||
|
sre = re.compile(r'\s*(t_[a-zA-Z_0-9]*)\s*=')
|
||
|
|
||
|
counthash = { }
|
||
|
linen = 1
|
||
|
for l in lines:
|
||
|
m = fre.match(l)
|
||
|
if not m:
|
||
|
m = sre.match(l)
|
||
|
if m:
|
||
|
name = m.group(1)
|
||
|
prev = counthash.get(name)
|
||
|
if not prev:
|
||
|
counthash[name] = linen
|
||
|
else:
|
||
|
self.log.error("%s:%d: Rule %s redefined. Previously defined on line %d",filename,linen,name,prev)
|
||
|
self.error = 1
|
||
|
linen += 1
|
||
|
|
||
|
# -----------------------------------------------------------------------------
|
||
|
# lex(module)
|
||
|
#
|
||
|
# Build all of the regular expression rules from definitions in the supplied module
|
||
|
# -----------------------------------------------------------------------------
|
||
|
def lex(module=None,object=None,debug=0,optimize=0,lextab="lextab",reflags=0,nowarn=0,outputdir="", debuglog=None, errorlog=None):
|
||
|
global lexer
|
||
|
ldict = None
|
||
|
stateinfo = { 'INITIAL' : 'inclusive'}
|
||
|
lexobj = Lexer()
|
||
|
lexobj.lexoptimize = optimize
|
||
|
global token,input
|
||
|
|
||
|
if errorlog is None:
|
||
|
errorlog = PlyLogger(sys.stderr)
|
||
|
|
||
|
if debug:
|
||
|
if debuglog is None:
|
||
|
debuglog = PlyLogger(sys.stderr)
|
||
|
|
||
|
# Get the module dictionary used for the lexer
|
||
|
if object: module = object
|
||
|
|
||
|
if module:
|
||
|
_items = [(k,getattr(module,k)) for k in dir(module)]
|
||
|
ldict = dict(_items)
|
||
|
else:
|
||
|
ldict = get_caller_module_dict(2)
|
||
|
|
||
|
# Collect parser information from the dictionary
|
||
|
linfo = LexerReflect(ldict,log=errorlog,reflags=reflags)
|
||
|
linfo.get_all()
|
||
|
if not optimize:
|
||
|
if linfo.validate_all():
|
||
|
raise SyntaxError("Can't build lexer")
|
||
|
|
||
|
if optimize and lextab:
|
||
|
try:
|
||
|
lexobj.readtab(lextab,ldict)
|
||
|
token = lexobj.token
|
||
|
input = lexobj.input
|
||
|
lexer = lexobj
|
||
|
return lexobj
|
||
|
|
||
|
except ImportError:
|
||
|
pass
|
||
|
|
||
|
# Dump some basic debugging information
|
||
|
if debug:
|
||
|
debuglog.info("lex: tokens = %r", linfo.tokens)
|
||
|
debuglog.info("lex: literals = %r", linfo.literals)
|
||
|
debuglog.info("lex: states = %r", linfo.stateinfo)
|
||
|
|
||
|
# Build a dictionary of valid token names
|
||
|
lexobj.lextokens = { }
|
||
|
for n in linfo.tokens:
|
||
|
lexobj.lextokens[n] = 1
|
||
|
|
||
|
# Get literals specification
|
||
|
if isinstance(linfo.literals,(list,tuple)):
|
||
|
lexobj.lexliterals = type(linfo.literals[0])().join(linfo.literals)
|
||
|
else:
|
||
|
lexobj.lexliterals = linfo.literals
|
||
|
|
||
|
# Get the stateinfo dictionary
|
||
|
stateinfo = linfo.stateinfo
|
||
|
|
||
|
regexs = { }
|
||
|
# Build the master regular expressions
|
||
|
for state in stateinfo:
|
||
|
regex_list = []
|
||
|
|
||
|
# Add rules defined by functions first
|
||
|
for fname, f in linfo.funcsym[state]:
|
||
|
line = func_code(f).co_firstlineno
|
||
|
file = func_code(f).co_filename
|
||
|
regex_list.append("(?P<%s>%s)" % (fname,f.__doc__))
|
||
|
if debug:
|
||
|
debuglog.info("lex: Adding rule %s -> '%s' (state '%s')",fname,f.__doc__, state)
|
||
|
|
||
|
# Now add all of the simple rules
|
||
|
for name,r in linfo.strsym[state]:
|
||
|
regex_list.append("(?P<%s>%s)" % (name,r))
|
||
|
if debug:
|
||
|
debuglog.info("lex: Adding rule %s -> '%s' (state '%s')",name,r, state)
|
||
|
|
||
|
regexs[state] = regex_list
|
||
|
|
||
|
# Build the master regular expressions
|
||
|
|
||
|
if debug:
|
||
|
debuglog.info("lex: ==== MASTER REGEXS FOLLOW ====")
|
||
|
|
||
|
for state in regexs:
|
||
|
lexre, re_text, re_names = _form_master_re(regexs[state],reflags,ldict,linfo.toknames)
|
||
|
lexobj.lexstatere[state] = lexre
|
||
|
lexobj.lexstateretext[state] = re_text
|
||
|
lexobj.lexstaterenames[state] = re_names
|
||
|
if debug:
|
||
|
for i in range(len(re_text)):
|
||
|
debuglog.info("lex: state '%s' : regex[%d] = '%s'",state, i, re_text[i])
|
||
|
|
||
|
# For inclusive states, we need to add the regular expressions from the INITIAL state
|
||
|
for state,stype in stateinfo.items():
|
||
|
if state != "INITIAL" and stype == 'inclusive':
|
||
|
lexobj.lexstatere[state].extend(lexobj.lexstatere['INITIAL'])
|
||
|
lexobj.lexstateretext[state].extend(lexobj.lexstateretext['INITIAL'])
|
||
|
lexobj.lexstaterenames[state].extend(lexobj.lexstaterenames['INITIAL'])
|
||
|
|
||
|
lexobj.lexstateinfo = stateinfo
|
||
|
lexobj.lexre = lexobj.lexstatere["INITIAL"]
|
||
|
lexobj.lexretext = lexobj.lexstateretext["INITIAL"]
|
||
|
lexobj.lexreflags = reflags
|
||
|
|
||
|
# Set up ignore variables
|
||
|
lexobj.lexstateignore = linfo.ignore
|
||
|
lexobj.lexignore = lexobj.lexstateignore.get("INITIAL","")
|
||
|
|
||
|
# Set up error functions
|
||
|
lexobj.lexstateerrorf = linfo.errorf
|
||
|
lexobj.lexerrorf = linfo.errorf.get("INITIAL",None)
|
||
|
if not lexobj.lexerrorf:
|
||
|
errorlog.warning("No t_error rule is defined")
|
||
|
|
||
|
# Check state information for ignore and error rules
|
||
|
for s,stype in stateinfo.items():
|
||
|
if stype == 'exclusive':
|
||
|
if not s in linfo.errorf:
|
||
|
errorlog.warning("No error rule is defined for exclusive state '%s'", s)
|
||
|
if not s in linfo.ignore and lexobj.lexignore:
|
||
|
errorlog.warning("No ignore rule is defined for exclusive state '%s'", s)
|
||
|
elif stype == 'inclusive':
|
||
|
if not s in linfo.errorf:
|
||
|
linfo.errorf[s] = linfo.errorf.get("INITIAL",None)
|
||
|
if not s in linfo.ignore:
|
||
|
linfo.ignore[s] = linfo.ignore.get("INITIAL","")
|
||
|
|
||
|
# Create global versions of the token() and input() functions
|
||
|
token = lexobj.token
|
||
|
input = lexobj.input
|
||
|
lexer = lexobj
|
||
|
|
||
|
# If in optimize mode, we write the lextab
|
||
|
if lextab and optimize:
|
||
|
lexobj.writetab(lextab,outputdir)
|
||
|
|
||
|
return lexobj
|
||
|
|
||
|
# -----------------------------------------------------------------------------
|
||
|
# runmain()
|
||
|
#
|
||
|
# This runs the lexer as a main program
|
||
|
# -----------------------------------------------------------------------------
|
||
|
|
||
|
def runmain(lexer=None,data=None):
|
||
|
if not data:
|
||
|
try:
|
||
|
filename = sys.argv[1]
|
||
|
f = open(filename)
|
||
|
data = f.read()
|
||
|
f.close()
|
||
|
except IndexError:
|
||
|
sys.stdout.write("Reading from standard input (type EOF to end):\n")
|
||
|
data = sys.stdin.read()
|
||
|
|
||
|
if lexer:
|
||
|
_input = lexer.input
|
||
|
else:
|
||
|
_input = input
|
||
|
_input(data)
|
||
|
if lexer:
|
||
|
_token = lexer.token
|
||
|
else:
|
||
|
_token = token
|
||
|
|
||
|
while 1:
|
||
|
tok = _token()
|
||
|
if not tok: break
|
||
|
sys.stdout.write("(%s,%r,%d,%d)\n" % (tok.type, tok.value, tok.lineno,tok.lexpos))
|
||
|
|
||
|
# -----------------------------------------------------------------------------
|
||
|
# @TOKEN(regex)
|
||
|
#
|
||
|
# This decorator function can be used to set the regex expression on a function
|
||
|
# when its docstring might need to be set in an alternative way
|
||
|
# -----------------------------------------------------------------------------
|
||
|
|
||
|
def TOKEN(r):
|
||
|
def set_doc(f):
|
||
|
if hasattr(r,"__call__"):
|
||
|
f.__doc__ = r.__doc__
|
||
|
else:
|
||
|
f.__doc__ = r
|
||
|
return f
|
||
|
return set_doc
|
||
|
|
||
|
# Alternative spelling of the TOKEN decorator
|
||
|
Token = TOKEN
|
||
|
|