diff options
| author | Balint Reczey <balint@balintreczey.hu> | 2016-08-03 23:28:28 +0200 |
|---|---|---|
| committer | João Valverde <j@v6e.pt> | 2016-08-04 08:20:24 +0000 |
| commit | d04be0149d1942e691030d20e52e94ed2eabfab6 (patch) | |
| tree | 2fb0b158c5e932fc3f360fc0677c723e6c494a06 /tools/yacc.py | |
| parent | 92eecfd25533147c793e483bd54a32afc14d2b8a (diff) | |
Ply parser updated to 3.8 from http://www.dabeaz.com/ply/
The Ubuntu packaged Ply 3.7 with Ubuntu 16.04's Python makes
ASN.1 based dissector generation fail.
Ply's API changed after 3.5 and the small change to asn2wrs.py
adapts to that.
The commit breaking the API in Ply's repository is the following:
commit af651673ba6117a0a5405055a92170fffd028106
Author: David Beazley <dave@dabeaz.com>
Date: Tue Apr 21 16:31:32 2015 -0500
Added optional support for defaulted states
Change-Id: I1db33fdcccf7c39ecdb0e435a5ea9183362471ad
Bug: 12621
Reviewed-on: https://code.wireshark.org/review/16864
Reviewed-by: Balint Reczey <balint@balintreczey.hu>
Petri-Dish: Balint Reczey <balint@balintreczey.hu>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: João Valverde <j@v6e.pt>
Tested-by: João Valverde <j@v6e.pt>
Diffstat (limited to 'tools/yacc.py')
| -rw-r--r--[-rwxr-xr-x] | tools/yacc.py | 2044 |
1 files changed, 1092 insertions, 952 deletions
diff --git a/tools/yacc.py b/tools/yacc.py index 49d83d78e5..e0c0cbaa35 100755..100644 --- a/tools/yacc.py +++ b/tools/yacc.py @@ -1,22 +1,22 @@ # ----------------------------------------------------------------------------- # ply: yacc.py # -# Copyright (C) 2001-2011, +# Copyright (C) 2001-2015, # David M. Beazley (Dabeaz LLC) # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: -# +# # * Redistributions of source code must retain the above copyright notice, -# this list of conditions and the following disclaimer. -# * Redistributions in binary form must reproduce the above copyright notice, +# this list of conditions and the following disclaimer. +# * Redistributions in binary form must reproduce the above copyright notice, # this list of conditions and the following disclaimer in the documentation -# and/or other materials provided with the distribution. +# and/or other materials provided with the distribution. # * Neither the name of the David Beazley or Dabeaz LLC may be used to # endorse or promote products derived from this software without -# specific prior written permission. +# specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT @@ -59,8 +59,16 @@ # own risk! # ---------------------------------------------------------------------------- -__version__ = "3.5" -__tabversion__ = "3.2" # Table version +import re +import types +import sys +import os.path +import inspect +import base64 +import warnings + +__version__ = '3.8' +__tabversion__ = '3.8' #----------------------------------------------------------------------------- # === User configurable parameters === @@ -68,7 +76,7 @@ __tabversion__ = "3.2" # Table version # Change these to modify the default behavior of yacc (if you wish) #----------------------------------------------------------------------------- -yaccdebug = 1 # Debugging mode. If set, yacc generates a +yaccdebug = True # Debugging mode. If set, yacc generates a # a 'parser.out' file in the current directory debug_file = 'parser.out' # Default name of the debugging file @@ -77,92 +85,75 @@ default_lr = 'LALR' # Default LR table generation method error_count = 3 # Number of symbols that must be shifted to leave recovery mode -yaccdevel = 0 # Set to True if developing yacc. This turns off optimized +yaccdevel = False # Set to True if developing yacc. This turns off optimized # implementations of certain functions. resultlimit = 40 # Size limit of results when running in debug mode. pickle_protocol = 0 # Protocol to use when writing pickle files -import re, types, sys, os.path, inspect - -# Compatibility function for python 2.6/3.0 -if sys.version_info[0] < 3: - def func_code(f): - return f.func_code -else: - def func_code(f): - return f.__code__ - # String type-checking compatibility if sys.version_info[0] < 3: string_types = basestring else: string_types = str -# Compatibility -try: - MAXINT = sys.maxint -except AttributeError: - MAXINT = sys.maxsize +MAXINT = sys.maxsize -# Python 2.x/3.0 compatibility. -def load_ply_lex(): - if sys.version_info[0] < 3: - import lex - else: - import ply.lex as lex - return lex - -# This object is a stand-in for a logging object created by the +# This object is a stand-in for a logging object created by the # logging module. PLY will use this by default to create things # such as the parser.out file. If a user wants more detailed # information, they can create their own logging object and pass # it into PLY. class PlyLogger(object): - def __init__(self,f): + def __init__(self, f): self.f = f - def debug(self,msg,*args,**kwargs): - self.f.write((msg % args) + "\n") - info = debug - def warning(self,msg,*args,**kwargs): - self.f.write("WARNING: "+ (msg % args) + "\n") + def debug(self, msg, *args, **kwargs): + self.f.write((msg % args) + '\n') + + info = debug - def error(self,msg,*args,**kwargs): - self.f.write("ERROR: " + (msg % args) + "\n") + def warning(self, msg, *args, **kwargs): + self.f.write('WARNING: ' + (msg % args) + '\n') + + def error(self, msg, *args, **kwargs): + self.f.write('ERROR: ' + (msg % args) + '\n') critical = debug # Null logger is used when no output is generated. Does nothing. class NullLogger(object): - def __getattribute__(self,name): + def __getattribute__(self, name): return self - def __call__(self,*args,**kwargs): + + def __call__(self, *args, **kwargs): return self - + # Exception raised for yacc-related errors -class YaccError(Exception): pass +class YaccError(Exception): + pass # Format the result message that the parser produces when running in debug mode. def format_result(r): repr_str = repr(r) - if '\n' in repr_str: repr_str = repr(repr_str) + if '\n' in repr_str: + repr_str = repr(repr_str) if len(repr_str) > resultlimit: - repr_str = repr_str[:resultlimit]+" ..." - result = "<%s @ 0x%x> (%s)" % (type(r).__name__,id(r),repr_str) + repr_str = repr_str[:resultlimit] + ' ...' + result = '<%s @ 0x%x> (%s)' % (type(r).__name__, id(r), repr_str) return result - # Format stack entries when the parser is running in debug mode def format_stack_entry(r): repr_str = repr(r) - if '\n' in repr_str: repr_str = repr(repr_str) + if '\n' in repr_str: + repr_str = repr(repr_str) if len(repr_str) < 16: return repr_str else: - return "<%s @ 0x%x>" % (type(r).__name__,id(r)) + return '<%s @ 0x%x>' % (type(r).__name__, id(r)) # Panic mode error recovery support. This feature is being reworked--much of the # code here is to offer a deprecation/backwards compatible transition @@ -170,7 +161,7 @@ def format_stack_entry(r): _errok = None _token = None _restart = None -_warnmsg = """PLY: Don't use global functions errok(), token(), and restart() in p_error(). +_warnmsg = '''PLY: Don't use global functions errok(), token(), and restart() in p_error(). Instead, invoke the methods on the associated parser instance: def p_error(p): @@ -179,8 +170,8 @@ Instead, invoke the methods on the associated parser instance: ... parser = yacc.yacc() -""" -import warnings +''' + def errok(): warnings.warn(_warnmsg) return _errok() @@ -194,13 +185,17 @@ def token(): return _token() # Utility function to call the p_error() function with some deprecation hacks -def call_errorfunc(errorfunc,token,parser): +def call_errorfunc(errorfunc, token, parser): global _errok, _token, _restart _errok = parser.errok _token = parser.token _restart = parser.restart r = errorfunc(token) - del _errok, _token, _restart + try: + del _errok, _token, _restart + except NameError: + pass + return r #----------------------------------------------------------------------------- # === LR Parsing Engine === @@ -220,8 +215,11 @@ def call_errorfunc(errorfunc,token,parser): # .endlexpos = Ending lex position (optional, set automatically) class YaccSymbol: - def __str__(self): return self.type - def __repr__(self): return str(self) + def __str__(self): + return self.type + + def __repr__(self): + return str(self) # This class is a wrapper around the objects actually passed to each # grammar rule. Index lookup and assignment actually assign the @@ -233,50 +231,50 @@ class YaccSymbol: # representing the range of positional information for a symbol. class YaccProduction: - def __init__(self,s,stack=None): + def __init__(self, s, stack=None): self.slice = s self.stack = stack self.lexer = None - self.parser= None - def __getitem__(self,n): + self.parser = None + + def __getitem__(self, n): if isinstance(n, slice): return [s.value for s in self.slice[n]] - elif n >= 0: + elif n >= 0: return self.slice[n].value - else: + else: return self.stack[n].value - def __setitem__(self,n,v): + def __setitem__(self, n, v): self.slice[n].value = v - def __getslice__(self,i,j): + def __getslice__(self, i, j): return [s.value for s in self.slice[i:j]] def __len__(self): return len(self.slice) - def lineno(self,n): - return getattr(self.slice[n],"lineno",0) + def lineno(self, n): + return getattr(self.slice[n], 'lineno', 0) - def set_lineno(self,n,lineno): + def set_lineno(self, n, lineno): self.slice[n].lineno = lineno - def linespan(self,n): - startline = getattr(self.slice[n],"lineno",0) - endline = getattr(self.slice[n],"endlineno",startline) - return startline,endline + def linespan(self, n): + startline = getattr(self.slice[n], 'lineno', 0) + endline = getattr(self.slice[n], 'endlineno', startline) + return startline, endline - def lexpos(self,n): - return getattr(self.slice[n],"lexpos",0) + def lexpos(self, n): + return getattr(self.slice[n], 'lexpos', 0) - def lexspan(self,n): - startpos = getattr(self.slice[n],"lexpos",0) - endpos = getattr(self.slice[n],"endlexpos",startpos) - return startpos,endpos + def lexspan(self, n): + startpos = getattr(self.slice[n], 'lexpos', 0) + endpos = getattr(self.slice[n], 'endlexpos', startpos) + return startpos, endpos def error(self): - raise SyntaxError - + raise SyntaxError # ----------------------------------------------------------------------------- # == LRParser == @@ -285,14 +283,16 @@ class YaccProduction: # ----------------------------------------------------------------------------- class LRParser: - def __init__(self,lrtab,errorf): + def __init__(self, lrtab, errorf): self.productions = lrtab.lr_productions - self.action = lrtab.lr_action - self.goto = lrtab.lr_goto - self.errorfunc = errorf + self.action = lrtab.lr_action + self.goto = lrtab.lr_goto + self.errorfunc = errorf + self.set_defaulted_states() + self.errorok = True def errok(self): - self.errorok = 1 + self.errorok = True def restart(self): del self.statestack[:] @@ -302,24 +302,42 @@ class LRParser: self.symstack.append(sym) self.statestack.append(0) - def parse(self,input=None,lexer=None,debug=0,tracking=0,tokenfunc=None): + # Defaulted state support. + # This method identifies parser states where there is only one possible reduction action. + # For such states, the parser can make a choose to make a rule reduction without consuming + # the next look-ahead token. This delayed invocation of the tokenizer can be useful in + # certain kinds of advanced parsing situations where the lexer and parser interact with + # each other or change states (i.e., manipulation of scope, lexer states, etc.). + # + # See: http://www.gnu.org/software/bison/manual/html_node/Default-Reductions.html#Default-Reductions + def set_defaulted_states(self): + self.defaulted_states = {} + for state, actions in self.action.items(): + rules = list(actions.values()) + if len(rules) == 1 and rules[0] < 0: + self.defaulted_states[state] = rules[0] + + def disable_defaulted_states(self): + self.defaulted_states = {} + + def parse(self, input=None, lexer=None, debug=False, tracking=False, tokenfunc=None): if debug or yaccdevel: - if isinstance(debug,int): + if isinstance(debug, int): debug = PlyLogger(sys.stderr) - return self.parsedebug(input,lexer,debug,tracking,tokenfunc) + return self.parsedebug(input, lexer, debug, tracking, tokenfunc) elif tracking: - return self.parseopt(input,lexer,debug,tracking,tokenfunc) + return self.parseopt(input, lexer, debug, tracking, tokenfunc) else: - return self.parseopt_notrack(input,lexer,debug,tracking,tokenfunc) - + return self.parseopt_notrack(input, lexer, debug, tracking, tokenfunc) + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! # parsedebug(). # # This is the debugging enabled version of parse(). All changes made to the - # parsing engine should be made here. For the non-debugging version, - # copy this code to a method parseopt() and delete all of the sections - # enclosed in: + # parsing engine should be made here. Optimized versions of this function + # are automatically created by the ply/ygen.py script. This script cuts out + # sections enclosed in markers such as this: # # #--! DEBUG # statements @@ -327,22 +345,24 @@ class LRParser: # # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! - def parsedebug(self,input=None,lexer=None,debug=None,tracking=0,tokenfunc=None): - lookahead = None # Current lookahead symbol - lookaheadstack = [ ] # Stack of lookahead symbols - actions = self.action # Local reference to action table (to avoid lookup on self.) - goto = self.goto # Local reference to goto table (to avoid lookup on self.) - prod = self.productions # Local reference to production list (to avoid lookup on self.) - pslice = YaccProduction(None) # Production object passed to grammar rules - errorcount = 0 # Used during error recovery - - # --! DEBUG - debug.info("PLY: PARSE DEBUG START") - # --! DEBUG + def parsedebug(self, input=None, lexer=None, debug=False, tracking=False, tokenfunc=None): + #--! parsedebug-start + lookahead = None # Current lookahead symbol + lookaheadstack = [] # Stack of lookahead symbols + actions = self.action # Local reference to action table (to avoid lookup on self.) + goto = self.goto # Local reference to goto table (to avoid lookup on self.) + prod = self.productions # Local reference to production list (to avoid lookup on self.) + defaulted_states = self.defaulted_states # Local reference to defaulted states + pslice = YaccProduction(None) # Production object passed to grammar rules + errorcount = 0 # Used during error recovery + + #--! DEBUG + debug.info('PLY: PARSE DEBUG START') + #--! DEBUG # If no lexer was given, we will try to use the lex module if not lexer: - lex = load_ply_lex() + from . import lex lexer = lex.lexer # Set up the lexer and parser objects on pslice @@ -354,19 +374,19 @@ class LRParser: lexer.input(input) if tokenfunc is None: - # Tokenize function - get_token = lexer.token + # Tokenize function + get_token = lexer.token else: - get_token = tokenfunc + get_token = tokenfunc # Set the parser() token method (sometimes used in error recovery) self.token = get_token # Set up the state and symbol stacks - statestack = [ ] # Stack of parsing states + statestack = [] # Stack of parsing states self.statestack = statestack - symstack = [ ] # Stack of grammar symbols + symstack = [] # Stack of grammar symbols self.symstack = symstack pslice.stack = symstack # Put in the production @@ -376,52 +396,59 @@ class LRParser: statestack.append(0) sym = YaccSymbol() - sym.type = "$end" + sym.type = '$end' symstack.append(sym) state = 0 - while 1: + while True: # Get the next symbol on the input. If a lookahead symbol # is already set, we just use that. Otherwise, we'll pull # the next token off of the lookaheadstack or from the lexer - # --! DEBUG + #--! DEBUG debug.debug('') debug.debug('State : %s', state) - # --! DEBUG + #--! DEBUG - if not lookahead: - if not lookaheadstack: - lookahead = get_token() # Get the next token - else: - lookahead = lookaheadstack.pop() + if state not in defaulted_states: if not lookahead: - lookahead = YaccSymbol() - lookahead.type = "$end" + if not lookaheadstack: + lookahead = get_token() # Get the next token + else: + lookahead = lookaheadstack.pop() + if not lookahead: + lookahead = YaccSymbol() + lookahead.type = '$end' + + # Check the action table + ltype = lookahead.type + t = actions[state].get(ltype) + else: + t = defaulted_states[state] + #--! DEBUG + debug.debug('Defaulted state %s: Reduce using %d', state, -t) + #--! DEBUG - # --! DEBUG + #--! DEBUG debug.debug('Stack : %s', - ("%s . %s" % (" ".join([xx.type for xx in symstack][1:]), str(lookahead))).lstrip()) - # --! DEBUG - - # Check the action table - ltype = lookahead.type - t = actions[state].get(ltype) + ('%s . %s' % (' '.join([xx.type for xx in symstack][1:]), str(lookahead))).lstrip()) + #--! DEBUG if t is not None: if t > 0: # shift a symbol on the stack statestack.append(t) state = t - - # --! DEBUG - debug.debug("Action : Shift and goto state %s", t) - # --! DEBUG + + #--! DEBUG + debug.debug('Action : Shift and goto state %s', t) + #--! DEBUG symstack.append(lookahead) lookahead = None # Decrease error count on successful shift - if errorcount: errorcount -=1 + if errorcount: + errorcount -= 1 continue if t < 0: @@ -435,44 +462,46 @@ class LRParser: sym.type = pname # Production name sym.value = None - # --! DEBUG + #--! DEBUG if plen: - debug.info("Action : Reduce rule [%s] with %s and goto state %d", p.str, "["+",".join([format_stack_entry(_v.value) for _v in symstack[-plen:]])+"]",-t) + debug.info('Action : Reduce rule [%s] with %s and goto state %d', p.str, + '['+','.join([format_stack_entry(_v.value) for _v in symstack[-plen:]])+']', + goto[statestack[-1-plen]][pname]) else: - debug.info("Action : Reduce rule [%s] with %s and goto state %d", p.str, [],-t) - - # --! DEBUG + debug.info('Action : Reduce rule [%s] with %s and goto state %d', p.str, [], + goto[statestack[-1]][pname]) + + #--! DEBUG if plen: targ = symstack[-plen-1:] targ[0] = sym - # --! TRACKING + #--! TRACKING if tracking: - t1 = targ[1] - sym.lineno = t1.lineno - sym.lexpos = t1.lexpos - t1 = targ[-1] - sym.endlineno = getattr(t1,"endlineno",t1.lineno) - sym.endlexpos = getattr(t1,"endlexpos",t1.lexpos) - - # --! TRACKING + t1 = targ[1] + sym.lineno = t1.lineno + sym.lexpos = t1.lexpos + t1 = targ[-1] + sym.endlineno = getattr(t1, 'endlineno', t1.lineno) + sym.endlexpos = getattr(t1, 'endlexpos', t1.lexpos) + #--! TRACKING # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! - # The code enclosed in this section is duplicated + # The code enclosed in this section is duplicated # below as a performance optimization. Make sure # changes get made in both locations. pslice.slice = targ - + try: # Call the grammar rule with our special slice object del symstack[-plen:] del statestack[-plen:] p.callable(pslice) - # --! DEBUG - debug.info("Result : %s", format_result(pslice[0])) - # --! DEBUG + #--! DEBUG + debug.info('Result : %s', format_result(pslice[0])) + #--! DEBUG symstack.append(sym) state = goto[statestack[-1]][pname] statestack.append(state) @@ -485,22 +514,22 @@ class LRParser: sym.type = 'error' lookahead = sym errorcount = error_count - self.errorok = 0 + self.errorok = False continue # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! - + else: - # --! TRACKING + #--! TRACKING if tracking: - sym.lineno = lexer.lineno - sym.lexpos = lexer.lexpos - # --! TRACKING + sym.lineno = lexer.lineno + sym.lexpos = lexer.lexpos + #--! TRACKING - targ = [ sym ] + targ = [sym] # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! - # The code enclosed in this section is duplicated + # The code enclosed in this section is duplicated # above as a performance optimization. Make sure # changes get made in both locations. @@ -509,9 +538,9 @@ class LRParser: try: # Call the grammar rule with our special slice object p.callable(pslice) - # --! DEBUG - debug.info("Result : %s", format_result(pslice[0])) - # --! DEBUG + #--! DEBUG + debug.info('Result : %s', format_result(pslice[0])) + #--! DEBUG symstack.append(sym) state = goto[statestack[-1]][pname] statestack.append(state) @@ -524,25 +553,25 @@ class LRParser: sym.type = 'error' lookahead = sym errorcount = error_count - self.errorok = 0 + self.errorok = False continue # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! if t == 0: n = symstack[-1] - result = getattr(n,"value",None) - # --! DEBUG - debug.info("Done : Returning %s", format_result(result)) - debug.info("PLY: PARSE DEBUG END") - # --! DEBUG + result = getattr(n, 'value', None) + #--! DEBUG + debug.info('Done : Returning %s', format_result(result)) + debug.info('PLY: PARSE DEBUG END') + #--! DEBUG return result - if t == None: + if t is None: - # --! DEBUG + #--! DEBUG debug.error('Error : %s', - ("%s . %s" % (" ".join([xx.type for xx in symstack][1:]), str(lookahead))).lstrip()) - # --! DEBUG + ('%s . %s' % (' '.join([xx.type for xx in symstack][1:]), str(lookahead))).lstrip()) + #--! DEBUG # We have some kind of parsing error here. To handle # this, we are going to push the current token onto @@ -556,12 +585,12 @@ class LRParser: # errorcount == 0. if errorcount == 0 or self.errorok: errorcount = error_count - self.errorok = 0 + self.errorok = False errtoken = lookahead - if errtoken.type == "$end": + if errtoken.type == '$end': errtoken = None # End of file! if self.errorfunc: - if errtoken and not hasattr(errtoken,'lexer'): + if errtoken and not hasattr(errtoken, 'lexer'): errtoken.lexer = lexer tok = call_errorfunc(self.errorfunc, errtoken, self) if self.errorok: @@ -573,14 +602,16 @@ class LRParser: continue else: if errtoken: - if hasattr(errtoken,"lineno"): lineno = lookahead.lineno - else: lineno = 0 + if hasattr(errtoken, 'lineno'): + lineno = lookahead.lineno + else: + lineno = 0 if lineno: - sys.stderr.write("yacc: Syntax error at line %d, token=%s\n" % (lineno, errtoken.type)) + sys.stderr.write('yacc: Syntax error at line %d, token=%s\n' % (lineno, errtoken.type)) else: - sys.stderr.write("yacc: Syntax error, token=%s" % errtoken.type) + sys.stderr.write('yacc: Syntax error, token=%s' % errtoken.type) else: - sys.stderr.write("yacc: Parse error in input. EOF\n") + sys.stderr.write('yacc: Parse error in input. EOF\n') return else: @@ -590,7 +621,7 @@ class LRParser: # entire parse has been rolled back and we're completely hosed. The token is # discarded and we just keep going. - if len(statestack) <= 1 and lookahead.type != "$end": + if len(statestack) <= 1 and lookahead.type != '$end': lookahead = None errtoken = None state = 0 @@ -602,7 +633,7 @@ class LRParser: # at the end of the file. nuke the top entry and generate an error token # Start nuking entries on the stack - if lookahead.type == "$end": + if lookahead.type == '$end': # Whoa. We're really hosed here. Bail out return @@ -611,56 +642,67 @@ class LRParser: if sym.type == 'error': # Hmmm. Error is on top of stack, we'll just nuke input # symbol and continue + #--! TRACKING if tracking: - sym.endlineno = getattr(lookahead,"lineno", sym.lineno) - sym.endlexpos = getattr(lookahead,"lexpos", sym.lexpos) + sym.endlineno = getattr(lookahead, 'lineno', sym.lineno) + sym.endlexpos = getattr(lookahead, 'lexpos', sym.lexpos) + #--! TRACKING lookahead = None continue + + # Create the error symbol for the first time and make it the new lookahead symbol t = YaccSymbol() t.type = 'error' - if hasattr(lookahead,"lineno"): - t.lineno = lookahead.lineno - if hasattr(lookahead,"lexpos"): - t.lexpos = lookahead.lexpos + + if hasattr(lookahead, 'lineno'): + t.lineno = t.endlineno = lookahead.lineno + if hasattr(lookahead, 'lexpos'): + t.lexpos = t.endlexpos = lookahead.lexpos t.value = lookahead lookaheadstack.append(lookahead) lookahead = t else: sym = symstack.pop() + #--! TRACKING if tracking: lookahead.lineno = sym.lineno lookahead.lexpos = sym.lexpos + #--! TRACKING statestack.pop() - state = statestack[-1] # Potential bug fix + state = statestack[-1] continue # Call an error function here - raise RuntimeError("yacc: internal parser error!!!\n") + raise RuntimeError('yacc: internal parser error!!!\n') + + #--! parsedebug-end # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! # parseopt(). # - # Optimized version of parse() method. DO NOT EDIT THIS CODE DIRECTLY. - # Edit the debug version above, then copy any modifications to the method - # below while removing #--! DEBUG sections. + # Optimized version of parse() method. DO NOT EDIT THIS CODE DIRECTLY! + # This code is automatically generated by the ply/ygen.py script. Make + # changes to the parsedebug() method instead. # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + def parseopt(self, input=None, lexer=None, debug=False, tracking=False, tokenfunc=None): + #--! parseopt-start + lookahead = None # Current lookahead symbol + lookaheadstack = [] # Stack of lookahead symbols + actions = self.action # Local reference to action table (to avoid lookup on self.) + goto = self.goto # Local reference to goto table (to avoid lookup on self.) + prod = self.productions # Local reference to production list (to avoid lookup on self.) + defaulted_states = self.defaulted_states # Local reference to defaulted states + pslice = YaccProduction(None) # Production object passed to grammar rules + errorcount = 0 # Used during error recovery - def parseopt(self,input=None,lexer=None,debug=0,tracking=0,tokenfunc=None): - lookahead = None # Current lookahead symbol - lookaheadstack = [ ] # Stack of lookahead symbols - actions = self.action # Local reference to action table (to avoid lookup on self.) - goto = self.goto # Local reference to goto table (to avoid lookup on self.) - prod = self.productions # Local reference to production list (to avoid lookup on self.) - pslice = YaccProduction(None) # Production object passed to grammar rules - errorcount = 0 # Used during error recovery # If no lexer was given, we will try to use the lex module if not lexer: - lex = load_ply_lex() + from . import lex lexer = lex.lexer - + # Set up the lexer and parser objects on pslice pslice.lexer = lexer pslice.parser = self @@ -670,19 +712,19 @@ class LRParser: lexer.input(input) if tokenfunc is None: - # Tokenize function - get_token = lexer.token + # Tokenize function + get_token = lexer.token else: - get_token = tokenfunc + get_token = tokenfunc # Set the parser() token method (sometimes used in error recovery) self.token = get_token # Set up the state and symbol stacks - statestack = [ ] # Stack of parsing states + statestack = [] # Stack of parsing states self.statestack = statestack - symstack = [ ] # Stack of grammar symbols + symstack = [] # Stack of grammar symbols self.symstack = symstack pslice.stack = symstack # Put in the production @@ -695,23 +737,28 @@ class LRParser: sym.type = '$end' symstack.append(sym) state = 0 - while 1: + while True: # Get the next symbol on the input. If a lookahead symbol # is already set, we just use that. Otherwise, we'll pull # the next token off of the lookaheadstack or from the lexer - if not lookahead: - if not lookaheadstack: - lookahead = get_token() # Get the next token - else: - lookahead = lookaheadstack.pop() + + if state not in defaulted_states: if not lookahead: - lookahead = YaccSymbol() - lookahead.type = '$end' + if not lookaheadstack: + lookahead = get_token() # Get the next token + else: + lookahead = lookaheadstack.pop() + if not lookahead: + lookahead = YaccSymbol() + lookahead.type = '$end' + + # Check the action table + ltype = lookahead.type + t = actions[state].get(ltype) + else: + t = defaulted_states[state] - # Check the action table - ltype = lookahead.type - t = actions[state].get(ltype) if t is not None: if t > 0: @@ -719,11 +766,13 @@ class LRParser: statestack.append(t) state = t + symstack.append(lookahead) lookahead = None # Decrease error count on successful shift - if errorcount: errorcount -=1 + if errorcount: + errorcount -= 1 continue if t < 0: @@ -737,28 +786,28 @@ class LRParser: sym.type = pname # Production name sym.value = None + if plen: targ = symstack[-plen-1:] targ[0] = sym - # --! TRACKING + #--! TRACKING if tracking: - t1 = targ[1] - sym.lineno = t1.lineno - sym.lexpos = t1.lexpos - t1 = targ[-1] - sym.endlineno = getattr(t1,"endlineno",t1.lineno) - sym.endlexpos = getattr(t1,"endlexpos",t1.lexpos) - - # --! TRACKING + t1 = targ[1] + sym.lineno = t1.lineno + sym.lexpos = t1.lexpos + t1 = targ[-1] + sym.endlineno = getattr(t1, 'endlineno', t1.lineno) + sym.endlexpos = getattr(t1, 'endlexpos', t1.lexpos) + #--! TRACKING # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! - # The code enclosed in this section is duplicated + # The code enclosed in this section is duplicated # below as a performance optimization. Make sure # changes get made in both locations. pslice.slice = targ - + try: # Call the grammar rule with our special slice object del symstack[-plen:] @@ -776,22 +825,22 @@ class LRParser: sym.type = 'error' lookahead = sym errorcount = error_count - self.errorok = 0 + self.errorok = False continue # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! - + else: - # --! TRACKING + #--! TRACKING if tracking: - sym.lineno = lexer.lineno - sym.lexpos = lexer.lexpos - # --! TRACKING + sym.lineno = lexer.lineno + sym.lexpos = lexer.lexpos + #--! TRACKING - targ = [ sym ] + targ = [sym] # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! - # The code enclosed in this section is duplicated + # The code enclosed in this section is duplicated # above as a performance optimization. Make sure # changes get made in both locations. @@ -812,15 +861,17 @@ class LRParser: sym.type = 'error' lookahead = sym errorcount = error_count - self.errorok = 0 + self.errorok = False continue # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! if t == 0: n = symstack[-1] - return getattr(n,"value",None) + result = getattr(n, 'value', None) + return result + + if t is None: - if t == None: # We have some kind of parsing error here. To handle # this, we are going to push the current token onto @@ -834,15 +885,14 @@ class LRParser: # errorcount == 0. if errorcount == 0 or self.errorok: errorcount = error_count - self.errorok = 0 + self.errorok = False errtoken = lookahead if errtoken.type == '$end': errtoken = None # End of file! if self.errorfunc: - if errtoken and not hasattr(errtoken,'lexer'): + if errtoken and not hasattr(errtoken, 'lexer'): errtoken.lexer = lexer tok = call_errorfunc(self.errorfunc, errtoken, self) - if self.errorok: # User must have done some kind of panic # mode recovery on their own. The @@ -852,14 +902,16 @@ class LRParser: continue else: if errtoken: - if hasattr(errtoken,"lineno"): lineno = lookahead.lineno - else: lineno = 0 + if hasattr(errtoken, 'lineno'): + lineno = lookahead.lineno + else: + lineno = 0 if lineno: - sys.stderr.write("yacc: Syntax error at line %d, token=%s\n" % (lineno, errtoken.type)) + sys.stderr.write('yacc: Syntax error at line %d, token=%s\n' % (lineno, errtoken.type)) else: - sys.stderr.write("yacc: Syntax error, token=%s" % errtoken.type) + sys.stderr.write('yacc: Syntax error, token=%s' % errtoken.type) else: - sys.stderr.write("yacc: Parse error in input. EOF\n") + sys.stderr.write('yacc: Parse error in input. EOF\n') return else: @@ -890,55 +942,67 @@ class LRParser: if sym.type == 'error': # Hmmm. Error is on top of stack, we'll just nuke input # symbol and continue + #--! TRACKING if tracking: - sym.endlineno = getattr(lookahead,"lineno", sym.lineno) - sym.endlexpos = getattr(lookahead,"lexpos", sym.lexpos) + sym.endlineno = getattr(lookahead, 'lineno', sym.lineno) + sym.endlexpos = getattr(lookahead, 'lexpos', sym.lexpos) + #--! TRACKING lookahead = None continue + + # Create the error symbol for the first time and make it the new lookahead symbol t = YaccSymbol() t.type = 'error' - if hasattr(lookahead,"lineno"): - t.lineno = lookahead.lineno - if hasattr(lookahead,"lexpos"): - t.lexpos = lookahead.lexpos + + if hasattr(lookahead, 'lineno'): + t.lineno = t.endlineno = lookahead.lineno + if hasattr(lookahead, 'lexpos'): + t.lexpos = t.endlexpos = lookahead.lexpos t.value = lookahead lookaheadstack.append(lookahead) lookahead = t else: sym = symstack.pop() + #--! TRACKING if tracking: lookahead.lineno = sym.lineno lookahead.lexpos = sym.lexpos + #--! TRACKING statestack.pop() - state = statestack[-1] # Potential bug fix + state = statestack[-1] continue # Call an error function here - raise RuntimeError("yacc: internal parser error!!!\n") + raise RuntimeError('yacc: internal parser error!!!\n') + + #--! parseopt-end # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! # parseopt_notrack(). # - # Optimized version of parseopt() with line number tracking removed. - # DO NOT EDIT THIS CODE DIRECTLY. Copy the optimized version and remove - # code in the #--! TRACKING sections + # Optimized version of parseopt() with line number tracking removed. + # DO NOT EDIT THIS CODE DIRECTLY. This code is automatically generated + # by the ply/ygen.py script. Make changes to the parsedebug() method instead. # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! - def parseopt_notrack(self,input=None,lexer=None,debug=0,tracking=0,tokenfunc=None): - lookahead = None # Current lookahead symbol - lookaheadstack = [ ] # Stack of lookahead symbols - actions = self.action # Local reference to action table (to avoid lookup on self.) - goto = self.goto # Local reference to goto table (to avoid lookup on self.) - prod = self.productions # Local reference to production list (to avoid lookup on self.) - pslice = YaccProduction(None) # Production object passed to grammar rules - errorcount = 0 # Used during error recovery + def parseopt_notrack(self, input=None, lexer=None, debug=False, tracking=False, tokenfunc=None): + #--! parseopt-notrack-start + lookahead = None # Current lookahead symbol + lookaheadstack = [] # Stack of lookahead symbols + actions = self.action # Local reference to action table (to avoid lookup on self.) + goto = self.goto # Local reference to goto table (to avoid lookup on self.) + prod = self.productions # Local reference to production list (to avoid lookup on self.) + defaulted_states = self.defaulted_states # Local reference to defaulted states + pslice = YaccProduction(None) # Production object passed to grammar rules + errorcount = 0 # Used during error recovery + # If no lexer was given, we will try to use the lex module if not lexer: - lex = load_ply_lex() + from . import lex lexer = lex.lexer - + # Set up the lexer and parser objects on pslice pslice.lexer = lexer pslice.parser = self @@ -948,19 +1012,19 @@ class LRParser: lexer.input(input) if tokenfunc is None: - # Tokenize function - get_token = lexer.token + # Tokenize function + get_token = lexer.token else: - get_token = tokenfunc + get_token = tokenfunc # Set the parser() token method (sometimes used in error recovery) self.token = get_token # Set up the state and symbol stacks - statestack = [ ] # Stack of parsing states + statestack = [] # Stack of parsing states self.statestack = statestack - symstack = [ ] # Stack of grammar symbols + symstack = [] # Stack of grammar symbols self.symstack = symstack pslice.stack = symstack # Put in the production @@ -973,23 +1037,28 @@ class LRParser: sym.type = '$end' symstack.append(sym) state = 0 - while 1: + while True: # Get the next symbol on the input. If a lookahead symbol # is already set, we just use that. Otherwise, we'll pull # the next token off of the lookaheadstack or from the lexer - if not lookahead: - if not lookaheadstack: - lookahead = get_token() # Get the next token - else: - lookahead = lookaheadstack.pop() + + if state not in defaulted_states: if not lookahead: - lookahead = YaccSymbol() - lookahead.type = '$end' + if not lookaheadstack: + lookahead = get_token() # Get the next token + else: + lookahead = lookaheadstack.pop() + if not lookahead: + lookahead = YaccSymbol() + lookahead.type = '$end' + + # Check the action table + ltype = lookahead.type + t = actions[state].get(ltype) + else: + t = defaulted_states[state] - # Check the action table - ltype = lookahead.type - t = actions[state].get(ltype) if t is not None: if t > 0: @@ -997,11 +1066,13 @@ class LRParser: statestack.append(t) state = t + symstack.append(lookahead) lookahead = None # Decrease error count on successful shift - if errorcount: errorcount -=1 + if errorcount: + errorcount -= 1 continue if t < 0: @@ -1015,17 +1086,19 @@ class LRParser: sym.type = pname # Production name sym.value = None + if plen: targ = symstack[-plen-1:] targ[0] = sym + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! - # The code enclosed in this section is duplicated + # The code enclosed in this section is duplicated # below as a performance optimization. Make sure # changes get made in both locations. pslice.slice = targ - + try: # Call the grammar rule with our special slice object del symstack[-plen:] @@ -1043,16 +1116,17 @@ class LRParser: sym.type = 'error' lookahead = sym errorcount = error_count - self.errorok = 0 + self.errorok = False continue # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! - + else: - targ = [ sym ] + + targ = [sym] # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! - # The code enclosed in this section is duplicated + # The code enclosed in this section is duplicated # above as a performance optimization. Make sure # changes get made in both locations. @@ -1073,15 +1147,17 @@ class LRParser: sym.type = 'error' lookahead = sym errorcount = error_count - self.errorok = 0 + self.errorok = False continue # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! if t == 0: n = symstack[-1] - return getattr(n,"value",None) + result = getattr(n, 'value', None) + return result + + if t is None: - if t == None: # We have some kind of parsing error here. To handle # this, we are going to push the current token onto @@ -1095,15 +1171,14 @@ class LRParser: # errorcount == 0. if errorcount == 0 or self.errorok: errorcount = error_count - self.errorok = 0 + self.errorok = False errtoken = lookahead if errtoken.type == '$end': errtoken = None # End of file! if self.errorfunc: - if errtoken and not hasattr(errtoken,'lexer'): + if errtoken and not hasattr(errtoken, 'lexer'): errtoken.lexer = lexer tok = call_errorfunc(self.errorfunc, errtoken, self) - if self.errorok: # User must have done some kind of panic # mode recovery on their own. The @@ -1113,14 +1188,16 @@ class LRParser: continue else: if errtoken: - if hasattr(errtoken,"lineno"): lineno = lookahead.lineno - else: lineno = 0 + if hasattr(errtoken, 'lineno'): + lineno = lookahead.lineno + else: + lineno = 0 if lineno: - sys.stderr.write("yacc: Syntax error at line %d, token=%s\n" % (lineno, errtoken.type)) + sys.stderr.write('yacc: Syntax error at line %d, token=%s\n' % (lineno, errtoken.type)) else: - sys.stderr.write("yacc: Syntax error, token=%s" % errtoken.type) + sys.stderr.write('yacc: Syntax error, token=%s' % errtoken.type) else: - sys.stderr.write("yacc: Parse error in input. EOF\n") + sys.stderr.write('yacc: Parse error in input. EOF\n') return else: @@ -1153,34 +1230,37 @@ class LRParser: # symbol and continue lookahead = None continue + + # Create the error symbol for the first time and make it the new lookahead symbol t = YaccSymbol() t.type = 'error' - if hasattr(lookahead,"lineno"): - t.lineno = lookahead.lineno - if hasattr(lookahead,"lexpos"): - t.lexpos = lookahead.lexpos + + if hasattr(lookahead, 'lineno'): + t.lineno = t.endlineno = lookahead.lineno + if hasattr(lookahead, 'lexpos'): + t.lexpos = t.endlexpos = lookahead.lexpos t.value = lookahead lookaheadstack.append(lookahead) lookahead = t else: - symstack.pop() + sym = symstack.pop() statestack.pop() - state = statestack[-1] # Potential bug fix + state = statestack[-1] continue # Call an error function here - raise RuntimeError("yacc: internal parser error!!!\n") + raise RuntimeError('yacc: internal parser error!!!\n') + + #--! parseopt-notrack-end # ----------------------------------------------------------------------------- # === Grammar Representation === # # The following functions, classes, and variables are used to represent and -# manipulate the rules that make up a grammar. +# manipulate the rules that make up a grammar. # ----------------------------------------------------------------------------- -import re - # regex matching identifiers _is_identifier = re.compile(r'^[a-zA-Z0-9_-]+$') @@ -1190,7 +1270,7 @@ _is_identifier = re.compile(r'^[a-zA-Z0-9_-]+$') # This class stores the raw information about a single production or grammar rule. # A grammar rule refers to a specification such as this: # -# expr : expr PLUS term +# expr : expr PLUS term # # Here are the basic attributes defined on all productions # @@ -1210,7 +1290,7 @@ _is_identifier = re.compile(r'^[a-zA-Z0-9_-]+$') class Production(object): reduced = 0 - def __init__(self,number,name,prod,precedence=('right',0),func=None,file='',line=0): + def __init__(self, number, name, prod, precedence=('right', 0), func=None, file='', line=0): self.name = name self.prod = tuple(prod) self.number = number @@ -1221,11 +1301,11 @@ class Production(object): self.prec = precedence # Internal settings used during table construction - + self.len = len(self.prod) # Length of the production # Create a list of unique production symbols used in the production - self.usyms = [ ] + self.usyms = [] for s in self.prod: if s not in self.usyms: self.usyms.append(s) @@ -1236,15 +1316,15 @@ class Production(object): # Create a string representation if self.prod: - self.str = "%s -> %s" % (self.name," ".join(self.prod)) + self.str = '%s -> %s' % (self.name, ' '.join(self.prod)) else: - self.str = "%s -> <empty>" % self.name + self.str = '%s -> <empty>' % self.name def __str__(self): return self.str def __repr__(self): - return "Production("+str(self)+")" + return 'Production(' + str(self) + ')' def __len__(self): return len(self.prod) @@ -1252,28 +1332,27 @@ class Production(object): def __nonzero__(self): return 1 - def __getitem__(self,index): + def __getitem__(self, index): return self.prod[index] - - # Return the nth lr_item from the production (or None if at the end) - def lr_item(self,n): - if n > len(self.prod): return None - p = LRItem(self,n) - # Precompute the list of productions immediately following. Hack. Remove later + # Return the nth lr_item from the production (or None if at the end) + def lr_item(self, n): + if n > len(self.prod): + return None + p = LRItem(self, n) + # Precompute the list of productions immediately following. try: p.lr_after = Prodnames[p.prod[n+1]] - except (IndexError,KeyError): + except (IndexError, KeyError): p.lr_after = [] try: p.lr_before = p.prod[n-1] except IndexError: p.lr_before = None - return p - + # Bind the production function name to a callable - def bind(self,pdict): + def bind(self, pdict): if self.func: self.callable = pdict[self.func] @@ -1282,7 +1361,7 @@ class Production(object): # actually used by the LR parsing engine, plus some additional # debugging information. class MiniProduction(object): - def __init__(self,str,name,len,func,file,line): + def __init__(self, str, name, len, func, file, line): self.name = name self.len = len self.func = func @@ -1290,13 +1369,15 @@ class MiniProduction(object): self.file = file self.line = line self.str = str + def __str__(self): return self.str + def __repr__(self): - return "MiniProduction(%s)" % self.str + return 'MiniProduction(%s)' % self.str # Bind the production function name to a callable - def bind(self,pdict): + def bind(self, pdict): if self.func: self.callable = pdict[self.func] @@ -1305,9 +1386,9 @@ class MiniProduction(object): # class LRItem # # This class represents a specific stage of parsing a production rule. For -# example: +# example: # -# expr : expr . PLUS term +# expr : expr . PLUS term # # In the above, the "." represents the current location of the parse. Here # basic attributes: @@ -1326,26 +1407,26 @@ class MiniProduction(object): # ----------------------------------------------------------------------------- class LRItem(object): - def __init__(self,p,n): + def __init__(self, p, n): self.name = p.name self.prod = list(p.prod) self.number = p.number self.lr_index = n - self.lookaheads = { } - self.prod.insert(n,".") + self.lookaheads = {} + self.prod.insert(n, '.') self.prod = tuple(self.prod) self.len = len(self.prod) self.usyms = p.usyms def __str__(self): if self.prod: - s = "%s -> %s" % (self.name," ".join(self.prod)) + s = '%s -> %s' % (self.name, ' '.join(self.prod)) else: - s = "%s -> <empty>" % self.name + s = '%s -> <empty>' % self.name return s def __repr__(self): - return "LRItem("+str(self)+")" + return 'LRItem(' + str(self) + ')' # ----------------------------------------------------------------------------- # rightmost_terminal() @@ -1368,21 +1449,22 @@ def rightmost_terminal(symbols, terminals): # This data is used for critical parts of the table generation process later. # ----------------------------------------------------------------------------- -class GrammarError(YaccError): pass +class GrammarError(YaccError): + pass class Grammar(object): - def __init__(self,terminals): + def __init__(self, terminals): self.Productions = [None] # A list of all of the productions. The first # entry is always reserved for the purpose of # building an augmented grammar - self.Prodnames = { } # A dictionary mapping the names of nonterminals to a list of all + self.Prodnames = {} # A dictionary mapping the names of nonterminals to a list of all # productions of that nonterminal. - self.Prodmap = { } # A dictionary that is only used to detect duplicate + self.Prodmap = {} # A dictionary that is only used to detect duplicate # productions. - self.Terminals = { } # A dictionary mapping the names of terminal symbols to a + self.Terminals = {} # A dictionary mapping the names of terminal symbols to a # list of the rules where they are used. for term in terminals: @@ -1390,17 +1472,17 @@ class Grammar(object): self.Terminals['error'] = [] - self.Nonterminals = { } # A dictionary mapping names of nonterminals to a list + self.Nonterminals = {} # A dictionary mapping names of nonterminals to a list # of rule numbers where they are used. - self.First = { } # A dictionary of precomputed FIRST(x) symbols + self.First = {} # A dictionary of precomputed FIRST(x) symbols - self.Follow = { } # A dictionary of precomputed FOLLOW(x) symbols + self.Follow = {} # A dictionary of precomputed FOLLOW(x) symbols - self.Precedence = { } # Precedence rules for each terminal. Contains tuples of the + self.Precedence = {} # Precedence rules for each terminal. Contains tuples of the # form ('right',level) or ('nonassoc', level) or ('left',level) - self.UsedPrecedence = { } # Precedence rules that were actually used by the grammer. + self.UsedPrecedence = set() # Precedence rules that were actually used by the grammer. # This is only used to provide error checking and to generate # a warning about unused precedence rules. @@ -1410,7 +1492,7 @@ class Grammar(object): def __len__(self): return len(self.Productions) - def __getitem__(self,index): + def __getitem__(self, index): return self.Productions[index] # ----------------------------------------------------------------------------- @@ -1421,14 +1503,14 @@ class Grammar(object): # # ----------------------------------------------------------------------------- - def set_precedence(self,term,assoc,level): - assert self.Productions == [None],"Must call set_precedence() before add_production()" + def set_precedence(self, term, assoc, level): + assert self.Productions == [None], 'Must call set_precedence() before add_production()' if term in self.Precedence: - raise GrammarError("Precedence already specified for terminal %r" % term) - if assoc not in ['left','right','nonassoc']: + raise GrammarError('Precedence already specified for terminal %r' % term) + if assoc not in ['left', 'right', 'nonassoc']: raise GrammarError("Associativity must be one of 'left','right', or 'nonassoc'") - self.Precedence[term] = (assoc,level) - + self.Precedence[term] = (assoc, level) + # ----------------------------------------------------------------------------- # add_production() # @@ -1446,72 +1528,74 @@ class Grammar(object): # are valid and that %prec is used correctly. # ----------------------------------------------------------------------------- - def add_production(self,prodname,syms,func=None,file='',line=0): + def add_production(self, prodname, syms, func=None, file='', line=0): if prodname in self.Terminals: - raise GrammarError("%s:%d: Illegal rule name %r. Already defined as a token" % (file,line,prodname)) + raise GrammarError('%s:%d: Illegal rule name %r. Already defined as a token' % (file, line, prodname)) if prodname == 'error': - raise GrammarError("%s:%d: Illegal rule name %r. error is a reserved word" % (file,line,prodname)) + raise GrammarError('%s:%d: Illegal rule name %r. error is a reserved word' % (file, line, prodname)) if not _is_identifier.match(prodname): - raise GrammarError("%s:%d: Illegal rule name %r" % (file,line,prodname)) + raise GrammarError('%s:%d: Illegal rule name %r' % (file, line, prodname)) - # Look for literal tokens - for n,s in enumerate(syms): + # Look for literal tokens + for n, s in enumerate(syms): if s[0] in "'\"": - try: - c = eval(s) - if (len(c) > 1): - raise GrammarError("%s:%d: Literal token %s in rule %r may only be a single character" % (file,line,s, prodname)) - if not c in self.Terminals: - self.Terminals[c] = [] - syms[n] = c - continue - except SyntaxError: - pass + try: + c = eval(s) + if (len(c) > 1): + raise GrammarError('%s:%d: Literal token %s in rule %r may only be a single character' % + (file, line, s, prodname)) + if c not in self.Terminals: + self.Terminals[c] = [] + syms[n] = c + continue + except SyntaxError: + pass if not _is_identifier.match(s) and s != '%prec': - raise GrammarError("%s:%d: Illegal name %r in rule %r" % (file,line,s, prodname)) - + raise GrammarError('%s:%d: Illegal name %r in rule %r' % (file, line, s, prodname)) + # Determine the precedence level if '%prec' in syms: if syms[-1] == '%prec': - raise GrammarError("%s:%d: Syntax error. Nothing follows %%prec" % (file,line)) + raise GrammarError('%s:%d: Syntax error. Nothing follows %%prec' % (file, line)) if syms[-2] != '%prec': - raise GrammarError("%s:%d: Syntax error. %%prec can only appear at the end of a grammar rule" % (file,line)) + raise GrammarError('%s:%d: Syntax error. %%prec can only appear at the end of a grammar rule' % + (file, line)) precname = syms[-1] prodprec = self.Precedence.get(precname) if not prodprec: - raise GrammarError("%s:%d: Nothing known about the precedence of %r" % (file,line,precname)) + raise GrammarError('%s:%d: Nothing known about the precedence of %r' % (file, line, precname)) else: - self.UsedPrecedence[precname] = 1 + self.UsedPrecedence.add(precname) del syms[-2:] # Drop %prec from the rule else: # If no %prec, precedence is determined by the rightmost terminal symbol - precname = rightmost_terminal(syms,self.Terminals) - prodprec = self.Precedence.get(precname,('right',0)) - + precname = rightmost_terminal(syms, self.Terminals) + prodprec = self.Precedence.get(precname, ('right', 0)) + # See if the rule is already in the rulemap - map = "%s -> %s" % (prodname,syms) + map = '%s -> %s' % (prodname, syms) if map in self.Prodmap: m = self.Prodmap[map] - raise GrammarError("%s:%d: Duplicate rule %s. " % (file,line, m) + - "Previous definition at %s:%d" % (m.file, m.line)) + raise GrammarError('%s:%d: Duplicate rule %s. ' % (file, line, m) + + 'Previous definition at %s:%d' % (m.file, m.line)) # From this point on, everything is valid. Create a new Production instance pnumber = len(self.Productions) - if not prodname in self.Nonterminals: - self.Nonterminals[prodname] = [ ] + if prodname not in self.Nonterminals: + self.Nonterminals[prodname] = [] # Add the production number to Terminals and Nonterminals for t in syms: if t in self.Terminals: self.Terminals[t].append(pnumber) else: - if not t in self.Nonterminals: - self.Nonterminals[t] = [ ] + if t not in self.Nonterminals: + self.Nonterminals[t] = [] self.Nonterminals[t].append(pnumber) # Create a production and add it to the list of productions - p = Production(pnumber,prodname,syms,prodprec,func,file,line) + p = Production(pnumber, prodname, syms, prodprec, func, file, line) self.Productions.append(p) self.Prodmap[map] = p @@ -1519,22 +1603,21 @@ class Grammar(object): try: self.Prodnames[prodname].append(p) except KeyError: - self.Prodnames[prodname] = [ p ] - return 0 + self.Prodnames[prodname] = [p] # ----------------------------------------------------------------------------- # set_start() # - # Sets the starting symbol and creates the augmented grammar. Production + # Sets the starting symbol and creates the augmented grammar. Production # rule 0 is S' -> start where start is the start symbol. # ----------------------------------------------------------------------------- - def set_start(self,start=None): + def set_start(self, start=None): if not start: start = self.Productions[1].name if start not in self.Nonterminals: - raise GrammarError("start symbol %s undefined" % start) - self.Productions[0] = Production(0,"S'",[start]) + raise GrammarError('start symbol %s undefined' % start) + self.Productions[0] = Production(0, "S'", [start]) self.Nonterminals[start].append(0) self.Start = start @@ -1546,26 +1629,20 @@ class Grammar(object): # ----------------------------------------------------------------------------- def find_unreachable(self): - + # Mark all symbols that are reachable from a symbol s def mark_reachable_from(s): - if reachable[s]: - # We've already reached symbol s. + if s in reachable: return - reachable[s] = 1 - for p in self.Prodnames.get(s,[]): + reachable.add(s) + for p in self.Prodnames.get(s, []): for r in p.prod: mark_reachable_from(r) - reachable = { } - for s in list(self.Terminals) + list(self.Nonterminals): - reachable[s] = 0 - - mark_reachable_from( self.Productions[0].prod[0] ) + reachable = set() + mark_reachable_from(self.Productions[0].prod[0]) + return [s for s in self.Nonterminals if s not in reachable] - return [s for s in list(self.Nonterminals) - if not reachable[s]] - # ----------------------------------------------------------------------------- # infinite_cycles() # @@ -1579,20 +1656,20 @@ class Grammar(object): # Terminals: for t in self.Terminals: - terminates[t] = 1 + terminates[t] = True - terminates['$end'] = 1 + terminates['$end'] = True # Nonterminals: # Initialize to false: for n in self.Nonterminals: - terminates[n] = 0 + terminates[n] = False # Then propagate termination until no change: - while 1: - some_change = 0 - for (n,pl) in self.Prodnames.items(): + while True: + some_change = False + for (n, pl) in self.Prodnames.items(): # Nonterminal n terminates iff any of its productions terminates. for p in pl: # Production p terminates iff all of its rhs symbols terminate. @@ -1600,19 +1677,19 @@ class Grammar(object): if not terminates[s]: # The symbol s does not terminate, # so production p does not terminate. - p_terminates = 0 + p_terminates = False break else: # didn't break from the loop, # so every symbol s terminates # so production p terminates. - p_terminates = 1 + p_terminates = True if p_terminates: # symbol n terminates! if not terminates[n]: - terminates[n] = 1 - some_change = 1 + terminates[n] = True + some_change = True # Don't need to consider any more productions for this n. break @@ -1620,9 +1697,9 @@ class Grammar(object): break infinite = [] - for (s,term) in terminates.items(): + for (s, term) in terminates.items(): if not term: - if not s in self.Prodnames and not s in self.Terminals and s != 'error': + if s not in self.Prodnames and s not in self.Terminals and s != 'error': # s is used-but-not-defined, and we've already warned of that, # so it would be overkill to say that it's also non-terminating. pass @@ -1631,22 +1708,22 @@ class Grammar(object): return infinite - # ----------------------------------------------------------------------------- # undefined_symbols() # # Find all symbols that were used the grammar, but not defined as tokens or # grammar rules. Returns a list of tuples (sym, prod) where sym in the symbol - # and prod is the production where the symbol was used. + # and prod is the production where the symbol was used. # ----------------------------------------------------------------------------- def undefined_symbols(self): result = [] for p in self.Productions: - if not p: continue + if not p: + continue for s in p.prod: - if not s in self.Prodnames and not s in self.Terminals and s != 'error': - result.append((s,p)) + if s not in self.Prodnames and s not in self.Terminals and s != 'error': + result.append((s, p)) return result # ----------------------------------------------------------------------------- @@ -1657,7 +1734,7 @@ class Grammar(object): # ----------------------------------------------------------------------------- def unused_terminals(self): unused_tok = [] - for s,v in self.Terminals.items(): + for s, v in self.Terminals.items(): if s != 'error' and not v: unused_tok.append(s) @@ -1672,7 +1749,7 @@ class Grammar(object): def unused_rules(self): unused_prod = [] - for s,v in self.Nonterminals.items(): + for s, v in self.Nonterminals.items(): if not v: p = self.Prodnames[s][0] unused_prod.append(p) @@ -1684,15 +1761,15 @@ class Grammar(object): # Returns a list of tuples (term,precedence) corresponding to precedence # rules that were never used by the grammar. term is the name of the terminal # on which precedence was applied and precedence is a string such as 'left' or - # 'right' corresponding to the type of precedence. + # 'right' corresponding to the type of precedence. # ----------------------------------------------------------------------------- def unused_precedence(self): unused = [] for termname in self.Precedence: if not (termname in self.Terminals or termname in self.UsedPrecedence): - unused.append((termname,self.Precedence[termname][0])) - + unused.append((termname, self.Precedence[termname][0])) + return unused # ------------------------------------------------------------------------- @@ -1703,19 +1780,20 @@ class Grammar(object): # During execution of compute_first1, the result may be incomplete. # Afterward (e.g., when called from compute_follow()), it will be complete. # ------------------------------------------------------------------------- - def _first(self,beta): + def _first(self, beta): # We are computing First(x1,x2,x3,...,xn) - result = [ ] + result = [] for x in beta: - x_produces_empty = 0 + x_produces_empty = False # Add all the non-<empty> symbols of First[x] to the result. for f in self.First[x]: if f == '<empty>': - x_produces_empty = 1 + x_produces_empty = True else: - if f not in result: result.append(f) + if f not in result: + result.append(f) if x_produces_empty: # We have to consider the next x in beta, @@ -1754,17 +1832,17 @@ class Grammar(object): self.First[n] = [] # Then propagate symbols until no change: - while 1: - some_change = 0 + while True: + some_change = False for n in self.Nonterminals: for p in self.Prodnames[n]: for f in self._first(p.prod): if f not in self.First[n]: - self.First[n].append( f ) - some_change = 1 + self.First[n].append(f) + some_change = True if not some_change: break - + return self.First # --------------------------------------------------------------------- @@ -1774,7 +1852,7 @@ class Grammar(object): # follow set is the set of all symbols that might follow a given # non-terminal. See the Dragon book, 2nd Ed. p. 189. # --------------------------------------------------------------------- - def compute_follow(self,start=None): + def compute_follow(self, start=None): # If already computed, return the result if self.Follow: return self.Follow @@ -1785,36 +1863,36 @@ class Grammar(object): # Add '$end' to the follow list of the start symbol for k in self.Nonterminals: - self.Follow[k] = [ ] + self.Follow[k] = [] if not start: start = self.Productions[1].name - self.Follow[start] = [ '$end' ] + self.Follow[start] = ['$end'] - while 1: - didadd = 0 + while True: + didadd = False for p in self.Productions[1:]: # Here is the production set - for i in range(len(p.prod)): - B = p.prod[i] + for i, B in enumerate(p.prod): if B in self.Nonterminals: # Okay. We got a non-terminal in a production fst = self._first(p.prod[i+1:]) - hasempty = 0 + hasempty = False for f in fst: if f != '<empty>' and f not in self.Follow[B]: self.Follow[B].append(f) - didadd = 1 + didadd = True if f == '<empty>': - hasempty = 1 + hasempty = True if hasempty or i == (len(p.prod)-1): # Add elements of follow(a) to follow(b) for f in self.Follow[p.name]: if f not in self.Follow[B]: self.Follow[B].append(f) - didadd = 1 - if not didadd: break + didadd = True + if not didadd: + break return self.Follow @@ -1838,15 +1916,15 @@ class Grammar(object): lastlri = p i = 0 lr_items = [] - while 1: + while True: if i > len(p): lri = None else: - lri = LRItem(p,i) + lri = LRItem(p, i) # Precompute the list of productions immediately following try: lri.lr_after = self.Prodnames[lri.prod[i+1]] - except (IndexError,KeyError): + except (IndexError, KeyError): lri.lr_after = [] try: lri.lr_before = lri.prod[i-1] @@ -1854,7 +1932,8 @@ class Grammar(object): lri.lr_before = None lastlri.lr_next = lri - if not lri: break + if not lri: + break lr_items.append(lri) lastlri = lri i += 1 @@ -1863,12 +1942,13 @@ class Grammar(object): # ----------------------------------------------------------------------------- # == Class LRTable == # -# This basic class represents a basic table of LR parsing information. +# This basic class represents a basic table of LR parsing information. # Methods for generating the tables are not defined here. They are defined # in the derived class LRGeneratedTable. # ----------------------------------------------------------------------------- -class VersionError(YaccError): pass +class VersionError(YaccError): + pass class LRTable(object): def __init__(self): @@ -1877,19 +1957,15 @@ class LRTable(object): self.lr_productions = None self.lr_method = None - def read_table(self,module): - if isinstance(module,types.ModuleType): + def read_table(self, module): + if isinstance(module, types.ModuleType): parsetab = module else: - if sys.version_info[0] < 3: - exec("import %s as parsetab" % module) - else: - env = { } - exec("import %s as parsetab" % module, env, env) - parsetab = env['parsetab'] + exec('import %s' % module) + parsetab = sys.modules[module] if parsetab._tabversion != __tabversion__: - raise VersionError("yacc table file version is out of date") + raise VersionError('yacc table file version is out of date') self.lr_action = parsetab._lr_action self.lr_goto = parsetab._lr_goto @@ -1901,17 +1977,20 @@ class LRTable(object): self.lr_method = parsetab._lr_method return parsetab._lr_signature - def read_pickle(self,filename): + def read_pickle(self, filename): try: import cPickle as pickle except ImportError: import pickle - in_f = open(filename,"rb") + if not os.path.exists(filename): + raise ImportError + + in_f = open(filename, 'rb') tabversion = pickle.load(in_f) if tabversion != __tabversion__: - raise VersionError("yacc table file version is out of date") + raise VersionError('yacc table file version is out of date') self.lr_method = pickle.load(in_f) signature = pickle.load(in_f) self.lr_action = pickle.load(in_f) @@ -1926,14 +2005,15 @@ class LRTable(object): return signature # Bind all production function names to callable objects in pdict - def bind_callables(self,pdict): + def bind_callables(self, pdict): for p in self.lr_productions: p.bind(pdict) - + + # ----------------------------------------------------------------------------- # === LR Generator === # -# The following classes and functions are used to generate LR parsing tables on +# The following classes and functions are used to generate LR parsing tables on # a grammar. # ----------------------------------------------------------------------------- @@ -1954,17 +2034,18 @@ class LRTable(object): # FP - Set-valued function # ------------------------------------------------------------------------------ -def digraph(X,R,FP): - N = { } +def digraph(X, R, FP): + N = {} for x in X: - N[x] = 0 + N[x] = 0 stack = [] - F = { } + F = {} for x in X: - if N[x] == 0: traverse(x,N,stack,F,X,R,FP) + if N[x] == 0: + traverse(x, N, stack, F, X, R, FP) return F -def traverse(x,N,stack,F,X,R,FP): +def traverse(x, N, stack, F, X, R, FP): stack.append(x) d = len(stack) N[x] = d @@ -1973,20 +2054,22 @@ def traverse(x,N,stack,F,X,R,FP): rel = R(x) # Get y's related to x for y in rel: if N[y] == 0: - traverse(y,N,stack,F,X,R,FP) - N[x] = min(N[x],N[y]) - for a in F.get(y,[]): - if a not in F[x]: F[x].append(a) + traverse(y, N, stack, F, X, R, FP) + N[x] = min(N[x], N[y]) + for a in F.get(y, []): + if a not in F[x]: + F[x].append(a) if N[x] == d: - N[stack[-1]] = MAXINT - F[stack[-1]] = F[x] - element = stack.pop() - while element != x: - N[stack[-1]] = MAXINT - F[stack[-1]] = F[x] - element = stack.pop() + N[stack[-1]] = MAXINT + F[stack[-1]] = F[x] + element = stack.pop() + while element != x: + N[stack[-1]] = MAXINT + F[stack[-1]] = F[x] + element = stack.pop() -class LALRError(YaccError): pass +class LALRError(YaccError): + pass # ----------------------------------------------------------------------------- # == LRGeneratedTable == @@ -1996,9 +2079,9 @@ class LALRError(YaccError): pass # ----------------------------------------------------------------------------- class LRGeneratedTable(LRTable): - def __init__(self,grammar,method='LALR',log=None): - if method not in ['SLR','LALR']: - raise LALRError("Unsupported method %s" % method) + def __init__(self, grammar, method='LALR', log=None): + if method not in ['SLR', 'LALR']: + raise LALRError('Unsupported method %s' % method) self.grammar = grammar self.lr_method = method @@ -2033,21 +2116,22 @@ class LRGeneratedTable(LRTable): # Compute the LR(0) closure operation on I, where I is a set of LR(0) items. - def lr0_closure(self,I): + def lr0_closure(self, I): self._add_count += 1 # Add everything in I to J J = I[:] - didadd = 1 + didadd = True while didadd: - didadd = 0 + didadd = False for j in J: for x in j.lr_after: - if getattr(x,"lr0_added",0) == self._add_count: continue + if getattr(x, 'lr0_added', 0) == self._add_count: + continue # Add B --> .G to J J.append(x.lr_next) x.lr0_added = self._add_count - didadd = 1 + didadd = True return J @@ -2058,26 +2142,27 @@ class LRGeneratedTable(LRTable): # objects). With uniqueness, we can later do fast set comparisons using # id(obj) instead of element-wise comparison. - def lr0_goto(self,I,x): + def lr0_goto(self, I, x): # First we look for a previously cached entry - g = self.lr_goto_cache.get((id(I),x)) - if g: return g + g = self.lr_goto_cache.get((id(I), x)) + if g: + return g # Now we generate the goto set in a way that guarantees uniqueness # of the result s = self.lr_goto_cache.get(x) if not s: - s = { } + s = {} self.lr_goto_cache[x] = s - gs = [ ] + gs = [] for p in I: n = p.lr_next if n and n.lr_before == x: s1 = s.get(id(n)) if not s1: - s1 = { } + s1 = {} s[id(n)] = s1 gs.append(n) s = s1 @@ -2088,13 +2173,12 @@ class LRGeneratedTable(LRTable): s['$end'] = g else: s['$end'] = gs - self.lr_goto_cache[(id(I),x)] = g + self.lr_goto_cache[(id(I), x)] = g return g # Compute the LR(0) sets of item function def lr0_items(self): - - C = [ self.lr0_closure([self.grammar.Productions[0].lr_next]) ] + C = [self.lr0_closure([self.grammar.Productions[0].lr_next])] i = 0 for I in C: self.lr0_cidhash[id(I)] = i @@ -2107,15 +2191,15 @@ class LRGeneratedTable(LRTable): i += 1 # Collect all of the symbols that could possibly be in the goto(I,X) sets - asyms = { } + asyms = {} for ii in I: for s in ii.usyms: asyms[s] = None for x in asyms: - g = self.lr0_goto(I,x) - if not g: continue - if id(g) in self.lr0_cidhash: continue + g = self.lr0_goto(I, x) + if not g or id(g) in self.lr0_cidhash: + continue self.lr0_cidhash[id(g)] = len(C) C.append(g) @@ -2150,19 +2234,21 @@ class LRGeneratedTable(LRTable): # ----------------------------------------------------------------------------- def compute_nullable_nonterminals(self): - nullable = {} + nullable = set() num_nullable = 0 - while 1: - for p in self.grammar.Productions[1:]: - if p.len == 0: - nullable[p.name] = 1 + while True: + for p in self.grammar.Productions[1:]: + if p.len == 0: + nullable.add(p.name) continue - for t in p.prod: - if not t in nullable: break - else: - nullable[p.name] = 1 - if len(nullable) == num_nullable: break - num_nullable = len(nullable) + for t in p.prod: + if t not in nullable: + break + else: + nullable.add(p.name) + if len(nullable) == num_nullable: + break + num_nullable = len(nullable) return nullable # ----------------------------------------------------------------------------- @@ -2176,16 +2262,16 @@ class LRGeneratedTable(LRTable): # The input C is the set of LR(0) items. # ----------------------------------------------------------------------------- - def find_nonterminal_transitions(self,C): - trans = [] - for state in range(len(C)): - for p in C[state]: - if p.lr_index < p.len - 1: - t = (state,p.prod[p.lr_index+1]) - if t[1] in self.grammar.Nonterminals: - if t not in trans: trans.append(t) - state = state + 1 - return trans + def find_nonterminal_transitions(self, C): + trans = [] + for stateno, state in enumerate(C): + for p in state: + if p.lr_index < p.len - 1: + t = (stateno, p.prod[p.lr_index+1]) + if t[1] in self.grammar.Nonterminals: + if t not in trans: + trans.append(t) + return trans # ----------------------------------------------------------------------------- # dr_relation() @@ -2196,21 +2282,22 @@ class LRGeneratedTable(LRTable): # Returns a list of terminals. # ----------------------------------------------------------------------------- - def dr_relation(self,C,trans,nullable): - dr_set = { } - state,N = trans + def dr_relation(self, C, trans, nullable): + dr_set = {} + state, N = trans terms = [] - g = self.lr0_goto(C[state],N) + g = self.lr0_goto(C[state], N) for p in g: - if p.lr_index < p.len - 1: - a = p.prod[p.lr_index+1] - if a in self.grammar.Terminals: - if a not in terms: terms.append(a) + if p.lr_index < p.len - 1: + a = p.prod[p.lr_index+1] + if a in self.grammar.Terminals: + if a not in terms: + terms.append(a) # This extra bit is to handle the start state if state == 0 and N == self.grammar.Productions[0].prod[0]: - terms.append('$end') + terms.append('$end') return terms @@ -2220,18 +2307,18 @@ class LRGeneratedTable(LRTable): # Computes the READS() relation (p,A) READS (t,C). # ----------------------------------------------------------------------------- - def reads_relation(self,C, trans, empty): + def reads_relation(self, C, trans, empty): # Look for empty transitions rel = [] state, N = trans - g = self.lr0_goto(C[state],N) - j = self.lr0_cidhash.get(id(g),-1) + g = self.lr0_goto(C[state], N) + j = self.lr0_cidhash.get(id(g), -1) for p in g: if p.lr_index < p.len - 1: - a = p.prod[p.lr_index + 1] - if a in empty: - rel.append((j,a)) + a = p.prod[p.lr_index + 1] + if a in empty: + rel.append((j, a)) return rel @@ -2263,8 +2350,7 @@ class LRGeneratedTable(LRTable): # # ----------------------------------------------------------------------------- - def compute_lookback_includes(self,C,trans,nullable): - + def compute_lookback_includes(self, C, trans, nullable): lookdict = {} # Dictionary of lookback relations includedict = {} # Dictionary of include relations @@ -2274,11 +2360,12 @@ class LRGeneratedTable(LRTable): dtrans[t] = 1 # Loop over all transitions and compute lookbacks and includes - for state,N in trans: + for state, N in trans: lookb = [] includes = [] for p in C[state]: - if p.name != N: continue + if p.name != N: + continue # Okay, we have a name match. We now follow the production all the way # through the state machine until we get the . on the right hand side @@ -2286,44 +2373,50 @@ class LRGeneratedTable(LRTable): lr_index = p.lr_index j = state while lr_index < p.len - 1: - lr_index = lr_index + 1 - t = p.prod[lr_index] - - # Check to see if this symbol and state are a non-terminal transition - if (j,t) in dtrans: - # Yes. Okay, there is some chance that this is an includes relation - # the only way to know for certain is whether the rest of the - # production derives empty - - li = lr_index + 1 - while li < p.len: - if p.prod[li] in self.grammar.Terminals: break # No forget it - if not p.prod[li] in nullable: break - li = li + 1 - else: - # Appears to be a relation between (j,t) and (state,N) - includes.append((j,t)) - - g = self.lr0_goto(C[j],t) # Go to next set - j = self.lr0_cidhash.get(id(g),-1) # Go to next state + lr_index = lr_index + 1 + t = p.prod[lr_index] + + # Check to see if this symbol and state are a non-terminal transition + if (j, t) in dtrans: + # Yes. Okay, there is some chance that this is an includes relation + # the only way to know for certain is whether the rest of the + # production derives empty + + li = lr_index + 1 + while li < p.len: + if p.prod[li] in self.grammar.Terminals: + break # No forget it + if p.prod[li] not in nullable: + break + li = li + 1 + else: + # Appears to be a relation between (j,t) and (state,N) + includes.append((j, t)) + + g = self.lr0_goto(C[j], t) # Go to next set + j = self.lr0_cidhash.get(id(g), -1) # Go to next state # When we get here, j is the final state, now we have to locate the production for r in C[j]: - if r.name != p.name: continue - if r.len != p.len: continue - i = 0 - # This look is comparing a production ". A B C" with "A B C ." - while i < r.lr_index: - if r.prod[i] != p.prod[i+1]: break - i = i + 1 - else: - lookb.append((j,r)) + if r.name != p.name: + continue + if r.len != p.len: + continue + i = 0 + # This look is comparing a production ". A B C" with "A B C ." + while i < r.lr_index: + if r.prod[i] != p.prod[i+1]: + break + i = i + 1 + else: + lookb.append((j, r)) for i in includes: - if not i in includedict: includedict[i] = [] - includedict[i].append((state,N)) - lookdict[(state,N)] = lookb + if i not in includedict: + includedict[i] = [] + includedict[i].append((state, N)) + lookdict[(state, N)] = lookb - return lookdict,includedict + return lookdict, includedict # ----------------------------------------------------------------------------- # compute_read_sets() @@ -2337,10 +2430,10 @@ class LRGeneratedTable(LRTable): # Returns a set containing the read sets # ----------------------------------------------------------------------------- - def compute_read_sets(self,C, ntrans, nullable): - FP = lambda x: self.dr_relation(C,x,nullable) - R = lambda x: self.reads_relation(C,x,nullable) - F = digraph(ntrans,R,FP) + def compute_read_sets(self, C, ntrans, nullable): + FP = lambda x: self.dr_relation(C, x, nullable) + R = lambda x: self.reads_relation(C, x, nullable) + F = digraph(ntrans, R, FP) return F # ----------------------------------------------------------------------------- @@ -2359,11 +2452,11 @@ class LRGeneratedTable(LRTable): # Returns a set containing the follow sets # ----------------------------------------------------------------------------- - def compute_follow_sets(self,ntrans,readsets,inclsets): - FP = lambda x: readsets[x] - R = lambda x: inclsets.get(x,[]) - F = digraph(ntrans,R,FP) - return F + def compute_follow_sets(self, ntrans, readsets, inclsets): + FP = lambda x: readsets[x] + R = lambda x: inclsets.get(x, []) + F = digraph(ntrans, R, FP) + return F # ----------------------------------------------------------------------------- # add_lookaheads() @@ -2377,15 +2470,16 @@ class LRGeneratedTable(LRTable): # in the lookbacks set # ----------------------------------------------------------------------------- - def add_lookaheads(self,lookbacks,followset): - for trans,lb in lookbacks.items(): + def add_lookaheads(self, lookbacks, followset): + for trans, lb in lookbacks.items(): # Loop over productions in lookback - for state,p in lb: - if not state in p.lookaheads: - p.lookaheads[state] = [] - f = followset.get(trans,[]) - for a in f: - if a not in p.lookaheads[state]: p.lookaheads[state].append(a) + for state, p in lb: + if state not in p.lookaheads: + p.lookaheads[state] = [] + f = followset.get(trans, []) + for a in f: + if a not in p.lookaheads[state]: + p.lookaheads[state].append(a) # ----------------------------------------------------------------------------- # add_lalr_lookaheads() @@ -2394,7 +2488,7 @@ class LRGeneratedTable(LRTable): # with LALR parsing # ----------------------------------------------------------------------------- - def add_lalr_lookaheads(self,C): + def add_lalr_lookaheads(self, C): # Determine all of the nullable nonterminals nullable = self.compute_nullable_nonterminals() @@ -2402,16 +2496,16 @@ class LRGeneratedTable(LRTable): trans = self.find_nonterminal_transitions(C) # Compute read sets - readsets = self.compute_read_sets(C,trans,nullable) + readsets = self.compute_read_sets(C, trans, nullable) # Compute lookback/includes relations - lookd, included = self.compute_lookback_includes(C,trans,nullable) + lookd, included = self.compute_lookback_includes(C, trans, nullable) # Compute LALR FOLLOW sets - followsets = self.compute_follow_sets(trans,readsets,included) + followsets = self.compute_follow_sets(trans, readsets, included) # Add all of the lookaheads - self.add_lookaheads(lookd,followsets) + self.add_lookaheads(lookd, followsets) # ----------------------------------------------------------------------------- # lr_parse_table() @@ -2425,9 +2519,9 @@ class LRGeneratedTable(LRTable): action = self.lr_action # Action array log = self.log # Logger for output - actionp = { } # Action production array (temporary) - - log.info("Parsing method: %s", self.lr_method) + actionp = {} # Action production array (temporary) + + log.info('Parsing method: %s', self.lr_method) # Step 1: Construct C = { I0, I1, ... IN}, collection of LR(0) items # This determines the number of states @@ -2441,23 +2535,23 @@ class LRGeneratedTable(LRTable): st = 0 for I in C: # Loop over each production in I - actlist = [ ] # List of actions - st_action = { } - st_actionp = { } - st_goto = { } - log.info("") - log.info("state %d", st) - log.info("") + actlist = [] # List of actions + st_action = {} + st_actionp = {} + st_goto = {} + log.info('') + log.info('state %d', st) + log.info('') for p in I: - log.info(" (%d) %s", p.number, str(p)) - log.info("") + log.info(' (%d) %s', p.number, p) + log.info('') for p in I: if p.len == p.lr_index + 1: if p.name == "S'": # Start symbol. Accept! - st_action["$end"] = 0 - st_actionp["$end"] = p + st_action['$end'] = 0 + st_actionp['$end'] = p else: # We are at the end of a production. Reduce! if self.lr_method == 'LALR': @@ -2465,7 +2559,7 @@ class LRGeneratedTable(LRTable): else: laheads = self.grammar.Follow[p.name] for a in laheads: - actlist.append((a,p,"reduce using rule %d (%s)" % (p.number,p))) + actlist.append((a, p, 'reduce using rule %d (%s)' % (p.number, p))) r = st_action.get(a) if r is not None: # Whoa. Have a shift/reduce or reduce/reduce conflict @@ -2473,23 +2567,23 @@ class LRGeneratedTable(LRTable): # Need to decide on shift or reduce here # By default we favor shifting. Need to add # some precedence rules here. - sprec,slevel = Productions[st_actionp[a].number].prec - rprec,rlevel = Precedence.get(a,('right',0)) + sprec, slevel = Productions[st_actionp[a].number].prec + rprec, rlevel = Precedence.get(a, ('right', 0)) if (slevel < rlevel) or ((slevel == rlevel) and (rprec == 'left')): # We really need to reduce here. st_action[a] = -p.number st_actionp[a] = p if not slevel and not rlevel: - log.info(" ! shift/reduce conflict for %s resolved as reduce",a) - self.sr_conflicts.append((st,a,'reduce')) + log.info(' ! shift/reduce conflict for %s resolved as reduce', a) + self.sr_conflicts.append((st, a, 'reduce')) Productions[p.number].reduced += 1 elif (slevel == rlevel) and (rprec == 'nonassoc'): st_action[a] = None else: # Hmmm. Guess we'll keep the shift if not rlevel: - log.info(" ! shift/reduce conflict for %s resolved as shift",a) - self.sr_conflicts.append((st,a,'shift')) + log.info(' ! shift/reduce conflict for %s resolved as shift', a) + self.sr_conflicts.append((st, a, 'shift')) elif r < 0: # Reduce/reduce conflict. In this case, we favor the rule # that was defined first in the grammar file @@ -2498,15 +2592,16 @@ class LRGeneratedTable(LRTable): if oldp.line > pp.line: st_action[a] = -p.number st_actionp[a] = p - chosenp,rejectp = pp,oldp + chosenp, rejectp = pp, oldp Productions[p.number].reduced += 1 Productions[oldp.number].reduced -= 1 else: - chosenp,rejectp = oldp,pp - self.rr_conflicts.append((st,chosenp,rejectp)) - log.info(" ! reduce/reduce conflict for %s resolved using rule %d (%s)", a,st_actionp[a].number, st_actionp[a]) + chosenp, rejectp = oldp, pp + self.rr_conflicts.append((st, chosenp, rejectp)) + log.info(' ! reduce/reduce conflict for %s resolved using rule %d (%s)', + a, st_actionp[a].number, st_actionp[a]) else: - raise LALRError("Unknown conflict in state %d" % st) + raise LALRError('Unknown conflict in state %d' % st) else: st_action[a] = -p.number st_actionp[a] = p @@ -2515,99 +2610,101 @@ class LRGeneratedTable(LRTable): i = p.lr_index a = p.prod[i+1] # Get symbol right after the "." if a in self.grammar.Terminals: - g = self.lr0_goto(I,a) - j = self.lr0_cidhash.get(id(g),-1) + g = self.lr0_goto(I, a) + j = self.lr0_cidhash.get(id(g), -1) if j >= 0: # We are in a shift state - actlist.append((a,p,"shift and go to state %d" % j)) + actlist.append((a, p, 'shift and go to state %d' % j)) r = st_action.get(a) if r is not None: # Whoa have a shift/reduce or shift/shift conflict if r > 0: if r != j: - raise LALRError("Shift/shift conflict in state %d" % st) + raise LALRError('Shift/shift conflict in state %d' % st) elif r < 0: # Do a precedence check. # - if precedence of reduce rule is higher, we reduce. # - if precedence of reduce is same and left assoc, we reduce. # - otherwise we shift - rprec,rlevel = Productions[st_actionp[a].number].prec - sprec,slevel = Precedence.get(a,('right',0)) + rprec, rlevel = Productions[st_actionp[a].number].prec + sprec, slevel = Precedence.get(a, ('right', 0)) if (slevel > rlevel) or ((slevel == rlevel) and (rprec == 'right')): # We decide to shift here... highest precedence to shift Productions[st_actionp[a].number].reduced -= 1 st_action[a] = j st_actionp[a] = p if not rlevel: - log.info(" ! shift/reduce conflict for %s resolved as shift",a) - self.sr_conflicts.append((st,a,'shift')) + log.info(' ! shift/reduce conflict for %s resolved as shift', a) + self.sr_conflicts.append((st, a, 'shift')) elif (slevel == rlevel) and (rprec == 'nonassoc'): st_action[a] = None else: # Hmmm. Guess we'll keep the reduce if not slevel and not rlevel: - log.info(" ! shift/reduce conflict for %s resolved as reduce",a) - self.sr_conflicts.append((st,a,'reduce')) + log.info(' ! shift/reduce conflict for %s resolved as reduce', a) + self.sr_conflicts.append((st, a, 'reduce')) else: - raise LALRError("Unknown conflict in state %d" % st) + raise LALRError('Unknown conflict in state %d' % st) else: st_action[a] = j st_actionp[a] = p # Print the actions associated with each terminal - _actprint = { } - for a,p,m in actlist: + _actprint = {} + for a, p, m in actlist: if a in st_action: if p is st_actionp[a]: - log.info(" %-15s %s",a,m) - _actprint[(a,m)] = 1 - log.info("") + log.info(' %-15s %s', a, m) + _actprint[(a, m)] = 1 + log.info('') # Print the actions that were not used. (debugging) not_used = 0 - for a,p,m in actlist: + for a, p, m in actlist: if a in st_action: if p is not st_actionp[a]: - if not (a,m) in _actprint: - log.debug(" ! %-15s [ %s ]",a,m) + if not (a, m) in _actprint: + log.debug(' ! %-15s [ %s ]', a, m) not_used = 1 - _actprint[(a,m)] = 1 + _actprint[(a, m)] = 1 if not_used: - log.debug("") + log.debug('') # Construct the goto table for this state - nkeys = { } + nkeys = {} for ii in I: for s in ii.usyms: if s in self.grammar.Nonterminals: nkeys[s] = None for n in nkeys: - g = self.lr0_goto(I,n) - j = self.lr0_cidhash.get(id(g),-1) + g = self.lr0_goto(I, n) + j = self.lr0_cidhash.get(id(g), -1) if j >= 0: st_goto[n] = j - log.info(" %-30s shift and go to state %d",n,j) + log.info(' %-30s shift and go to state %d', n, j) action[st] = st_action actionp[st] = st_actionp goto[st] = st_goto st += 1 - # ----------------------------------------------------------------------------- # write() # # This function writes the LR parsing tables to a file # ----------------------------------------------------------------------------- - def write_table(self,modulename,outputdir='',signature=""): - basemodulename = modulename.split(".")[-1] - filename = os.path.join(outputdir,basemodulename) + ".py" + def write_table(self, tabmodule, outputdir='', signature=''): + if isinstance(tabmodule, types.ModuleType): + raise IOError("Won't overwrite existing tabmodule") + + basemodulename = tabmodule.split('.')[-1] + filename = os.path.join(outputdir, basemodulename) + '.py' try: - f = open(filename,"w") + f = open(filename, 'w') - f.write(""" + f.write(''' # %s # This file is automatically generated. Do not edit. _tabversion = %r @@ -2615,105 +2712,103 @@ _tabversion = %r _lr_method = %r _lr_signature = %r - """ % (filename, __tabversion__, self.lr_method, signature)) + ''' % (os.path.basename(filename), __tabversion__, self.lr_method, signature)) # Change smaller to 0 to go back to original tables smaller = 1 # Factor out names to try and make smaller if smaller: - items = { } - - for s,nd in self.lr_action.items(): - for name,v in nd.items(): - i = items.get(name) - if not i: - i = ([],[]) - items[name] = i - i[0].append(s) - i[1].append(v) - - f.write("\n_lr_action_items = {") - for k,v in items.items(): - f.write("%r:([" % k) + items = {} + + for s, nd in self.lr_action.items(): + for name, v in nd.items(): + i = items.get(name) + if not i: + i = ([], []) + items[name] = i + i[0].append(s) + i[1].append(v) + + f.write('\n_lr_action_items = {') + for k, v in items.items(): + f.write('%r:([' % k) for i in v[0]: - f.write("%r," % i) - f.write("],[") + f.write('%r,' % i) + f.write('],[') for i in v[1]: - f.write("%r," % i) + f.write('%r,' % i) - f.write("]),") - f.write("}\n") + f.write(']),') + f.write('}\n') - f.write(""" -_lr_action = { } + f.write(''' +_lr_action = {} for _k, _v in _lr_action_items.items(): for _x,_y in zip(_v[0],_v[1]): - if not _x in _lr_action: _lr_action[_x] = { } + if not _x in _lr_action: _lr_action[_x] = {} _lr_action[_x][_k] = _y del _lr_action_items -""") +''') else: - f.write("\n_lr_action = { "); - for k,v in self.lr_action.items(): - f.write("(%r,%r):%r," % (k[0],k[1],v)) - f.write("}\n"); + f.write('\n_lr_action = { ') + for k, v in self.lr_action.items(): + f.write('(%r,%r):%r,' % (k[0], k[1], v)) + f.write('}\n') if smaller: # Factor out names to try and make smaller - items = { } - - for s,nd in self.lr_goto.items(): - for name,v in nd.items(): - i = items.get(name) - if not i: - i = ([],[]) - items[name] = i - i[0].append(s) - i[1].append(v) - - f.write("\n_lr_goto_items = {") - for k,v in items.items(): - f.write("%r:([" % k) + items = {} + + for s, nd in self.lr_goto.items(): + for name, v in nd.items(): + i = items.get(name) + if not i: + i = ([], []) + items[name] = i + i[0].append(s) + i[1].append(v) + + f.write('\n_lr_goto_items = {') + for k, v in items.items(): + f.write('%r:([' % k) for i in v[0]: - f.write("%r," % i) - f.write("],[") + f.write('%r,' % i) + f.write('],[') for i in v[1]: - f.write("%r," % i) + f.write('%r,' % i) - f.write("]),") - f.write("}\n") + f.write(']),') + f.write('}\n') - f.write(""" -_lr_goto = { } + f.write(''' +_lr_goto = {} for _k, _v in _lr_goto_items.items(): - for _x,_y in zip(_v[0],_v[1]): - if not _x in _lr_goto: _lr_goto[_x] = { } + for _x, _y in zip(_v[0], _v[1]): + if not _x in _lr_goto: _lr_goto[_x] = {} _lr_goto[_x][_k] = _y del _lr_goto_items -""") +''') else: - f.write("\n_lr_goto = { "); - for k,v in self.lr_goto.items(): - f.write("(%r,%r):%r," % (k[0],k[1],v)) - f.write("}\n"); + f.write('\n_lr_goto = { ') + for k, v in self.lr_goto.items(): + f.write('(%r,%r):%r,' % (k[0], k[1], v)) + f.write('}\n') # Write production table - f.write("_lr_productions = [\n") + f.write('_lr_productions = [\n') for p in self.lr_productions: if p.func: - f.write(" (%r,%r,%d,%r,%r,%d),\n" % (p.str,p.name, p.len, p.func,p.file,p.line)) + f.write(' (%r,%r,%d,%r,%r,%d),\n' % (p.str, p.name, p.len, + p.func, os.path.basename(p.file), p.line)) else: - f.write(" (%r,%r,%d,None,None,None),\n" % (str(p),p.name, p.len)) - f.write("]\n") + f.write(' (%r,%r,%d,None,None,None),\n' % (str(p), p.name, p.len)) + f.write(']\n') f.close() - except IOError: - e = sys.exc_info()[1] - sys.stderr.write("Unable to create %r\n" % filename) - sys.stderr.write(str(e)+"\n") - return + except IOError as e: + raise # ----------------------------------------------------------------------------- @@ -2722,26 +2817,25 @@ del _lr_goto_items # This function pickles the LR parsing tables to a supplied file object # ----------------------------------------------------------------------------- - def pickle_table(self,filename,signature=""): + def pickle_table(self, filename, signature=''): try: import cPickle as pickle except ImportError: import pickle - outf = open(filename,"wb") - pickle.dump(__tabversion__,outf,pickle_protocol) - pickle.dump(self.lr_method,outf,pickle_protocol) - pickle.dump(signature,outf,pickle_protocol) - pickle.dump(self.lr_action,outf,pickle_protocol) - pickle.dump(self.lr_goto,outf,pickle_protocol) - - outp = [] - for p in self.lr_productions: - if p.func: - outp.append((p.str,p.name, p.len, p.func,p.file,p.line)) - else: - outp.append((str(p),p.name,p.len,None,None,None)) - pickle.dump(outp,outf,pickle_protocol) - outf.close() + with open(filename, 'wb') as outf: + pickle.dump(__tabversion__, outf, pickle_protocol) + pickle.dump(self.lr_method, outf, pickle_protocol) + pickle.dump(signature, outf, pickle_protocol) + pickle.dump(self.lr_action, outf, pickle_protocol) + pickle.dump(self.lr_goto, outf, pickle_protocol) + + outp = [] + for p in self.lr_productions: + if p.func: + outp.append((p.str, p.name, p.len, p.func, os.path.basename(p.file), p.line)) + else: + outp.append((str(p), p.name, p.len, None, None, None)) + pickle.dump(outp, outf, pickle_protocol) # ----------------------------------------------------------------------------- # === INTROSPECTION === @@ -2759,26 +2853,18 @@ del _lr_goto_items # ----------------------------------------------------------------------------- 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 + f = sys._getframe(levels) + ldict = f.f_globals.copy() + if f.f_globals != f.f_locals: + ldict.update(f.f_locals) + return ldict # ----------------------------------------------------------------------------- # parse_grammar() # # This takes a raw grammar rule string and parses it into production data # ----------------------------------------------------------------------------- -def parse_grammar(doc,file,line): +def parse_grammar(doc, file, line): grammar = [] # Split the doc string into lines pstrings = doc.splitlines() @@ -2787,12 +2873,13 @@ def parse_grammar(doc,file,line): for ps in pstrings: dline += 1 p = ps.split() - if not p: continue + if not p: + continue try: if p[0] == '|': # This is a continuation of a previous rule if not lastp: - raise SyntaxError("%s:%d: Misplaced '|'" % (file,dline)) + raise SyntaxError("%s:%d: Misplaced '|'" % (file, dline)) prodname = lastp syms = p[1:] else: @@ -2801,13 +2888,13 @@ def parse_grammar(doc,file,line): syms = p[2:] assign = p[1] if assign != ':' and assign != '::=': - raise SyntaxError("%s:%d: Syntax error. Expected ':'" % (file,dline)) + raise SyntaxError("%s:%d: Syntax error. Expected ':'" % (file, dline)) - grammar.append((file,dline,prodname,syms)) + grammar.append((file, dline, prodname, syms)) except SyntaxError: raise except Exception: - raise SyntaxError("%s:%d: Syntax error in rule %r" % (file,dline,ps.strip())) + raise SyntaxError('%s:%d: Syntax error in rule %r' % (file, dline, ps.strip())) return grammar @@ -2819,14 +2906,14 @@ def parse_grammar(doc,file,line): # etc. # ----------------------------------------------------------------------------- class ParserReflect(object): - def __init__(self,pdict,log=None): + def __init__(self, pdict, log=None): self.pdict = pdict self.start = None self.error_func = None self.tokens = None - self.modules = {} + self.modules = set() self.grammar = [] - self.error = 0 + self.error = False if log is None: self.log = PlyLogger(sys.stderr) @@ -2840,7 +2927,7 @@ class ParserReflect(object): self.get_tokens() self.get_precedence() self.get_pfunctions() - + # Validate all of the information def validate_all(self): self.validate_start() @@ -2862,15 +2949,19 @@ class ParserReflect(object): if self.start: sig.update(self.start.encode('latin-1')) if self.prec: - sig.update("".join(["".join(p) for p in self.prec]).encode('latin-1')) + sig.update(''.join([''.join(p) for p in self.prec]).encode('latin-1')) if self.tokens: - sig.update(" ".join(self.tokens).encode('latin-1')) + sig.update(' '.join(self.tokens).encode('latin-1')) for f in self.pfuncs: if f[3]: sig.update(f[3].encode('latin-1')) - except (TypeError,ValueError): + except (TypeError, ValueError): pass - return sig.digest() + + digest = base64.b16encode(sig.digest()) + if sys.version_info[0] >= 3: + digest = digest.decode('latin-1') + return digest # ----------------------------------------------------------------------------- # validate_modules() @@ -2887,13 +2978,13 @@ class ParserReflect(object): # Match def p_funcname( fre = re.compile(r'\s*def\s+(p_[a-zA-Z_0-9]*)\(') - for module in self.modules.keys(): + for module in self.modules: lines, linen = inspect.getsourcelines(module) - counthash = { } - for linen,l in enumerate(lines): + counthash = {} + for linen, line in enumerate(lines): linen += 1 - m = fre.match(l) + m = fre.match(line) if m: name = m.group(1) prev = counthash.get(name) @@ -2901,7 +2992,8 @@ class ParserReflect(object): counthash[name] = linen else: filename = inspect.getsourcefile(module) - self.log.warning("%s:%d: Function %s redefined. Previously defined on line %d", filename,linen,name,prev) + self.log.warning('%s:%d: Function %s redefined. Previously defined on line %d', + filename, linen, name, prev) # Get the start symbol def get_start(self): @@ -2920,41 +3012,41 @@ class ParserReflect(object): # Validate the error function def validate_error_func(self): if self.error_func: - if isinstance(self.error_func,types.FunctionType): + if isinstance(self.error_func, types.FunctionType): ismethod = 0 elif isinstance(self.error_func, types.MethodType): ismethod = 1 else: self.log.error("'p_error' defined, but is not a function or method") - self.error = 1 + self.error = True return - eline = func_code(self.error_func).co_firstlineno - efile = func_code(self.error_func).co_filename + eline = self.error_func.__code__.co_firstlineno + efile = self.error_func.__code__.co_filename module = inspect.getmodule(self.error_func) - self.modules[module] = 1 + self.modules.add(module) - argcount = func_code(self.error_func).co_argcount - ismethod + argcount = self.error_func.__code__.co_argcount - ismethod if argcount != 1: - self.log.error("%s:%d: p_error() requires 1 argument",efile,eline) - self.error = 1 + self.log.error('%s:%d: p_error() requires 1 argument', efile, eline) + self.error = True # Get the tokens map def get_tokens(self): - tokens = self.pdict.get("tokens") + tokens = self.pdict.get('tokens') if not tokens: - self.log.error("No token list is defined") - self.error = 1 + self.log.error('No token list is defined') + self.error = True return - if not isinstance(tokens,(list, tuple)): - self.log.error("tokens must be a list or tuple") - self.error = 1 + if not isinstance(tokens, (list, tuple)): + self.log.error('tokens must be a list or tuple') + self.error = True return - + if not tokens: - self.log.error("tokens is empty") - self.error = 1 + self.log.error('tokens is empty') + self.error = True return self.tokens = tokens @@ -2964,46 +3056,46 @@ class ParserReflect(object): # Validate the tokens. if 'error' in self.tokens: self.log.error("Illegal token name 'error'. Is a reserved word") - self.error = 1 + self.error = True return - terminals = {} + terminals = set() for n in self.tokens: if n in terminals: - self.log.warning("Token %r multiply defined", n) - terminals[n] = 1 + self.log.warning('Token %r multiply defined', n) + terminals.add(n) # Get the precedence map (if any) def get_precedence(self): - self.prec = self.pdict.get("precedence") + self.prec = self.pdict.get('precedence') # Validate and parse the precedence map def validate_precedence(self): preclist = [] if self.prec: - if not isinstance(self.prec,(list,tuple)): - self.log.error("precedence must be a list or tuple") - self.error = 1 + if not isinstance(self.prec, (list, tuple)): + self.log.error('precedence must be a list or tuple') + self.error = True return - for level,p in enumerate(self.prec): - if not isinstance(p,(list,tuple)): - self.log.error("Bad precedence table") - self.error = 1 + for level, p in enumerate(self.prec): + if not isinstance(p, (list, tuple)): + self.log.error('Bad precedence table') + self.error = True return if len(p) < 2: - self.log.error("Malformed precedence entry %s. Must be (assoc, term, ..., term)",p) - self.error = 1 + self.log.error('Malformed precedence entry %s. Must be (assoc, term, ..., term)', p) + self.error = True return assoc = p[0] if not isinstance(assoc, string_types): - self.log.error("precedence associativity must be a string") - self.error = 1 + self.log.error('precedence associativity must be a string') + self.error = True return for term in p[1:]: if not isinstance(term, string_types): - self.log.error("precedence items must be strings") - self.error = 1 + self.log.error('precedence items must be strings') + self.error = True return preclist.append((term, assoc, level+1)) self.preclist = preclist @@ -3012,25 +3104,30 @@ class ParserReflect(object): def get_pfunctions(self): p_functions = [] for name, item in self.pdict.items(): - if not name.startswith('p_'): continue - if name == 'p_error': continue - if isinstance(item,(types.FunctionType,types.MethodType)): - line = func_code(item).co_firstlineno + if not name.startswith('p_') or name == 'p_error': + continue + if isinstance(item, (types.FunctionType, types.MethodType)): + line = item.__code__.co_firstlineno module = inspect.getmodule(item) - p_functions.append((line,module,name,item.__doc__)) - - # Sort all of the actions by line number - p_functions.sort() + p_functions.append((line, module, name, item.__doc__)) + + # Sort all of the actions by line number; make sure to stringify + # modules to make them sortable, since `line` may not uniquely sort all + # p functions + p_functions.sort(key=lambda p_function: ( + p_function[0], + str(p_function[1]), + p_function[2], + p_function[3])) self.pfuncs = p_functions - # Validate all of the p_functions def validate_pfunctions(self): grammar = [] # Check for non-empty symbols if len(self.pfuncs) == 0: - self.log.error("no rules of the form p_rulename are defined") - self.error = 1 + self.log.error('no rules of the form p_rulename are defined') + self.error = True return for line, module, name, doc in self.pfuncs: @@ -3040,45 +3137,48 @@ class ParserReflect(object): reqargs = 2 else: reqargs = 1 - if func_code(func).co_argcount > reqargs: - self.log.error("%s:%d: Rule %r has too many arguments",file,line,func.__name__) - self.error = 1 - elif func_code(func).co_argcount < reqargs: - self.log.error("%s:%d: Rule %r requires an argument",file,line,func.__name__) - self.error = 1 + if func.__code__.co_argcount > reqargs: + self.log.error('%s:%d: Rule %r has too many arguments', file, line, func.__name__) + self.error = True + elif func.__code__.co_argcount < reqargs: + self.log.error('%s:%d: Rule %r requires an argument', file, line, func.__name__) + self.error = True elif not func.__doc__: - self.log.warning("%s:%d: No documentation string specified in function %r (ignored)",file,line,func.__name__) + self.log.warning('%s:%d: No documentation string specified in function %r (ignored)', + file, line, func.__name__) else: try: - parsed_g = parse_grammar(doc,file,line) + parsed_g = parse_grammar(doc, file, line) for g in parsed_g: grammar.append((name, g)) - except SyntaxError: - e = sys.exc_info()[1] + except SyntaxError as e: self.log.error(str(e)) - self.error = 1 + self.error = True # Looks like a valid grammar rule # Mark the file in which defined. - self.modules[module] = 1 + self.modules.add(module) # Secondary validation step that looks for p_ definitions that are not functions # or functions that look like they might be grammar rules. - for n,v in self.pdict.items(): - if n.startswith('p_') and isinstance(v, (types.FunctionType, types.MethodType)): continue - if n.startswith('t_'): continue + for n, v in self.pdict.items(): + if n.startswith('p_') and isinstance(v, (types.FunctionType, types.MethodType)): + continue + if n.startswith('t_'): + continue if n.startswith('p_') and n != 'p_error': - self.log.warning("%r not defined as a function", n) - if ((isinstance(v,types.FunctionType) and func_code(v).co_argcount == 1) or - (isinstance(v,types.MethodType) and func_code(v).co_argcount == 2)): - try: - doc = v.__doc__.split(" ") - if doc[1] == ':': - self.log.warning("%s:%d: Possible grammar rule %r defined without p_ prefix", - func_code(v).co_filename, func_code(v).co_firstlineno,n) - except Exception: - pass + self.log.warning('%r not defined as a function', n) + if ((isinstance(v, types.FunctionType) and v.__code__.co_argcount == 1) or + (isinstance(v, types.MethodType) and v.__func__.__code__.co_argcount == 2)): + if v.__doc__: + try: + doc = v.__doc__.split(' ') + if doc[1] == ':': + self.log.warning('%s:%d: Possible grammar rule %r defined without p_ prefix', + v.__code__.co_filename, v.__code__.co_firstlineno, n) + except IndexError: + pass self.grammar = grammar @@ -3088,14 +3188,17 @@ class ParserReflect(object): # Build a parser # ----------------------------------------------------------------------------- -def yacc(method='LALR', debug=yaccdebug, module=None, tabmodule=tab_module, start=None, - check_recursion=1, optimize=0, write_tables=1, debugfile=debug_file,outputdir='', - debuglog=None, errorlog = None, picklefile=None): +def yacc(method='LALR', debug=yaccdebug, module=None, tabmodule=tab_module, start=None, + check_recursion=True, optimize=False, write_tables=True, debugfile=debug_file, + outputdir=None, debuglog=None, errorlog=None, picklefile=None): - global parse # Reference to the parsing method of the last built parser + if tabmodule is None: + tabmodule = tab_module - # If pickling is enabled, table files are not created + # Reference to the parsing method of the last built parser + global parse + # If pickling is enabled, table files are not created if picklefile: write_tables = 0 @@ -3104,17 +3207,50 @@ def yacc(method='LALR', debug=yaccdebug, module=None, tabmodule=tab_module, star # Get the module dictionary used for the parser if module: - _items = [(k,getattr(module,k)) for k in dir(module)] + _items = [(k, getattr(module, k)) for k in dir(module)] pdict = dict(_items) + # If no __file__ attribute is available, try to obtain it from the __module__ instead + if '__file__' not in pdict: + pdict['__file__'] = sys.modules[pdict['__module__']].__file__ else: pdict = get_caller_module_dict(2) + if outputdir is None: + # If no output directory is set, the location of the output files + # is determined according to the following rules: + # - If tabmodule specifies a package, files go into that package directory + # - Otherwise, files go in the same directory as the specifying module + if isinstance(tabmodule, types.ModuleType): + srcfile = tabmodule.__file__ + else: + if '.' not in tabmodule: + srcfile = pdict['__file__'] + else: + parts = tabmodule.split('.') + pkgname = '.'.join(parts[:-1]) + exec('import %s' % pkgname) + srcfile = getattr(sys.modules[pkgname], '__file__', '') + outputdir = os.path.dirname(srcfile) + + # Determine if the module is package of a package or not. + # If so, fix the tabmodule setting so that tables load correctly + pkg = pdict.get('__package__') + if pkg and isinstance(tabmodule, str): + if '.' not in tabmodule: + tabmodule = pkg + '.' + tabmodule + + + + # Set start symbol if it's specified directly using an argument + if start is not None: + pdict['start'] = start + # Collect parser information from the dictionary - pinfo = ParserReflect(pdict,log=errorlog) + pinfo = ParserReflect(pdict, log=errorlog) pinfo.get_all() if pinfo.error: - raise YaccError("Unable to build parser") + raise YaccError('Unable to build parser') # Check signature against table files (if any) signature = pinfo.signature() @@ -3129,35 +3265,36 @@ def yacc(method='LALR', debug=yaccdebug, module=None, tabmodule=tab_module, star if optimize or (read_signature == signature): try: lr.bind_callables(pinfo.pdict) - parser = LRParser(lr,pinfo.error_func) + parser = LRParser(lr, pinfo.error_func) parse = parser.parse return parser - except Exception: - e = sys.exc_info()[1] - errorlog.warning("There was a problem loading the table file: %s", repr(e)) - except VersionError: - e = sys.exc_info() + except Exception as e: + errorlog.warning('There was a problem loading the table file: %r', e) + except VersionError as e: errorlog.warning(str(e)) - except Exception: + except ImportError: pass if debuglog is None: if debug: - debuglog = PlyLogger(open(debugfile,"w")) + try: + debuglog = PlyLogger(open(os.path.join(outputdir, debugfile), 'w')) + except IOError as e: + errorlog.warning("Couldn't open %r. %s" % (debugfile, e)) + debuglog = NullLogger() else: debuglog = NullLogger() - debuglog.info("Created by PLY version %s (http://www.dabeaz.com/ply)", __version__) + debuglog.info('Created by PLY version %s (http://www.dabeaz.com/ply)', __version__) - - errors = 0 + errors = False # Validate the parser information if pinfo.validate_all(): - raise YaccError("Unable to build parser") - + raise YaccError('Unable to build parser') + if not pinfo.error_func: - errorlog.warning("no p_error() function is defined") + errorlog.warning('no p_error() function is defined') # Create a grammar object grammar = Grammar(pinfo.tokens) @@ -3165,20 +3302,18 @@ def yacc(method='LALR', debug=yaccdebug, module=None, tabmodule=tab_module, star # Set precedence level for terminals for term, assoc, level in pinfo.preclist: try: - grammar.set_precedence(term,assoc,level) - except GrammarError: - e = sys.exc_info()[1] - errorlog.warning("%s",str(e)) + grammar.set_precedence(term, assoc, level) + except GrammarError as e: + errorlog.warning('%s', e) # Add productions to the grammar for funcname, gram in pinfo.grammar: file, line, prodname, syms = gram try: - grammar.add_production(prodname,syms,funcname,file,line) - except GrammarError: - e = sys.exc_info()[1] - errorlog.error("%s",str(e)) - errors = 1 + grammar.add_production(prodname, syms, funcname, file, line) + except GrammarError as e: + errorlog.error('%s', e) + errors = True # Set the grammar start symbols try: @@ -3186,146 +3321,151 @@ def yacc(method='LALR', debug=yaccdebug, module=None, tabmodule=tab_module, star grammar.set_start(pinfo.start) else: grammar.set_start(start) - except GrammarError: - e = sys.exc_info()[1] + except GrammarError as e: errorlog.error(str(e)) - errors = 1 + errors = True if errors: - raise YaccError("Unable to build parser") + raise YaccError('Unable to build parser') # Verify the grammar structure undefined_symbols = grammar.undefined_symbols() for sym, prod in undefined_symbols: - errorlog.error("%s:%d: Symbol %r used, but not defined as a token or a rule",prod.file,prod.line,sym) - errors = 1 + errorlog.error('%s:%d: Symbol %r used, but not defined as a token or a rule', prod.file, prod.line, sym) + errors = True unused_terminals = grammar.unused_terminals() if unused_terminals: - debuglog.info("") - debuglog.info("Unused terminals:") - debuglog.info("") + debuglog.info('') + debuglog.info('Unused terminals:') + debuglog.info('') for term in unused_terminals: - errorlog.warning("Token %r defined, but not used", term) - debuglog.info(" %s", term) + errorlog.warning('Token %r defined, but not used', term) + debuglog.info(' %s', term) # Print out all productions to the debug log if debug: - debuglog.info("") - debuglog.info("Grammar") - debuglog.info("") - for n,p in enumerate(grammar.Productions): - debuglog.info("Rule %-5d %s", n, p) + debuglog.info('') + debuglog.info('Grammar') + debuglog.info('') + for n, p in enumerate(grammar.Productions): + debuglog.info('Rule %-5d %s', n, p) # Find unused non-terminals unused_rules = grammar.unused_rules() for prod in unused_rules: - errorlog.warning("%s:%d: Rule %r defined, but not used", prod.file, prod.line, prod.name) + errorlog.warning('%s:%d: Rule %r defined, but not used', prod.file, prod.line, prod.name) if len(unused_terminals) == 1: - errorlog.warning("There is 1 unused token") + errorlog.warning('There is 1 unused token') if len(unused_terminals) > 1: - errorlog.warning("There are %d unused tokens", len(unused_terminals)) + errorlog.warning('There are %d unused tokens', len(unused_terminals)) if len(unused_rules) == 1: - errorlog.warning("There is 1 unused rule") + errorlog.warning('There is 1 unused rule') if len(unused_rules) > 1: - errorlog.warning("There are %d unused rules", len(unused_rules)) + errorlog.warning('There are %d unused rules', len(unused_rules)) if debug: - debuglog.info("") - debuglog.info("Terminals, with rules where they appear") - debuglog.info("") + debuglog.info('') + debuglog.info('Terminals, with rules where they appear') + debuglog.info('') terms = list(grammar.Terminals) terms.sort() for term in terms: - debuglog.info("%-20s : %s", term, " ".join([str(s) for s in grammar.Terminals[term]])) - - debuglog.info("") - debuglog.info("Nonterminals, with rules where they appear") - debuglog.info("") + debuglog.info('%-20s : %s', term, ' '.join([str(s) for s in grammar.Terminals[term]])) + + debuglog.info('') + debuglog.info('Nonterminals, with rules where they appear') + debuglog.info('') nonterms = list(grammar.Nonterminals) nonterms.sort() for nonterm in nonterms: - debuglog.info("%-20s : %s", nonterm, " ".join([str(s) for s in grammar.Nonterminals[nonterm]])) - debuglog.info("") + debuglog.info('%-20s : %s', nonterm, ' '.join([str(s) for s in grammar.Nonterminals[nonterm]])) + debuglog.info('') if check_recursion: unreachable = grammar.find_unreachable() for u in unreachable: - errorlog.warning("Symbol %r is unreachable",u) + errorlog.warning('Symbol %r is unreachable', u) infinite = grammar.infinite_cycles() for inf in infinite: - errorlog.error("Infinite recursion detected for symbol %r", inf) - errors = 1 - + errorlog.error('Infinite recursion detected for symbol %r', inf) + errors = True + unused_prec = grammar.unused_precedence() for term, assoc in unused_prec: - errorlog.error("Precedence rule %r defined for unknown symbol %r", assoc, term) - errors = 1 + errorlog.error('Precedence rule %r defined for unknown symbol %r', assoc, term) + errors = True if errors: - raise YaccError("Unable to build parser") - + raise YaccError('Unable to build parser') + # Run the LRGeneratedTable on the grammar if debug: - errorlog.debug("Generating %s tables", method) - - lr = LRGeneratedTable(grammar,method,debuglog) + errorlog.debug('Generating %s tables', method) + + lr = LRGeneratedTable(grammar, method, debuglog) if debug: num_sr = len(lr.sr_conflicts) # Report shift/reduce and reduce/reduce conflicts if num_sr == 1: - errorlog.warning("1 shift/reduce conflict") + errorlog.warning('1 shift/reduce conflict') elif num_sr > 1: - errorlog.warning("%d shift/reduce conflicts", num_sr) + errorlog.warning('%d shift/reduce conflicts', num_sr) num_rr = len(lr.rr_conflicts) if num_rr == 1: - errorlog.warning("1 reduce/reduce conflict") + errorlog.warning('1 reduce/reduce conflict') elif num_rr > 1: - errorlog.warning("%d reduce/reduce conflicts", num_rr) + errorlog.warning('%d reduce/reduce conflicts', num_rr) # Write out conflicts to the output file if debug and (lr.sr_conflicts or lr.rr_conflicts): - debuglog.warning("") - debuglog.warning("Conflicts:") - debuglog.warning("") + debuglog.warning('') + debuglog.warning('Conflicts:') + debuglog.warning('') for state, tok, resolution in lr.sr_conflicts: - debuglog.warning("shift/reduce conflict for %s in state %d resolved as %s", tok, state, resolution) - - already_reported = {} + debuglog.warning('shift/reduce conflict for %s in state %d resolved as %s', tok, state, resolution) + + already_reported = set() for state, rule, rejected in lr.rr_conflicts: - if (state,id(rule),id(rejected)) in already_reported: + if (state, id(rule), id(rejected)) in already_reported: continue - debuglog.warning("reduce/reduce conflict in state %d resolved using rule (%s)", state, rule) - debuglog.warning("rejected rule (%s) in state %d", rejected,state) - errorlog.warning("reduce/reduce conflict in state %d resolved using rule (%s)", state, rule) - errorlog.warning("rejected rule (%s) in state %d", rejected, state) - already_reported[state,id(rule),id(rejected)] = 1 - + debuglog.warning('reduce/reduce conflict in state %d resolved using rule (%s)', state, rule) + debuglog.warning('rejected rule (%s) in state %d', rejected, state) + errorlog.warning('reduce/reduce conflict in state %d resolved using rule (%s)', state, rule) + errorlog.warning('rejected rule (%s) in state %d', rejected, state) + already_reported.add((state, id(rule), id(rejected))) + warned_never = [] for state, rule, rejected in lr.rr_conflicts: if not rejected.reduced and (rejected not in warned_never): - debuglog.warning("Rule (%s) is never reduced", rejected) - errorlog.warning("Rule (%s) is never reduced", rejected) + debuglog.warning('Rule (%s) is never reduced', rejected) + errorlog.warning('Rule (%s) is never reduced', rejected) warned_never.append(rejected) # Write the table file if requested if write_tables: - lr.write_table(tabmodule,outputdir,signature) + try: + lr.write_table(tabmodule, outputdir, signature) + except IOError as e: + errorlog.warning("Couldn't create %r. %s" % (tabmodule, e)) # Write a pickled version of the tables if picklefile: - lr.pickle_table(picklefile,signature) + try: + lr.pickle_table(picklefile, signature) + except IOError as e: + errorlog.warning("Couldn't create %r. %s" % (picklefile, e)) # Build the parser lr.bind_callables(pinfo.pdict) - parser = LRParser(lr,pinfo.error_func) + parser = LRParser(lr, pinfo.error_func) parse = parser.parse return parser |