FM / ply

/opt/alt/python37/lib/python3.7/site-packages/ply/

/opt/alt/python37/lib/python3.7/site-packages/ply

Name	Size	Mode	Actions
__pycache__/	-	0755	rm
cpp.py	33368	0644	edit dl rm
ctokens.py	3177	0644	edit dl rm
lex.py	42889	0644	edit dl rm
yacc.py	135805	0644	edit dl rm
ygen.py	2251	0644	edit dl rm
__init__.py	102	0644	edit dl rm

Edit: /opt/alt/python37/lib/python3.7/site-packages/ply/yacc.py (135805B)

# -----------------------------------------------------------------------------
# ply: yacc.py
#
# 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 in the documentation
#   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.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
# -----------------------------------------------------------------------------
#
# This implements an LR parser that is constructed from grammar rules defined
# as Python functions. The grammer is specified by supplying the BNF inside
# Python documentation strings.  The inspiration for this technique was borrowed
# from John Aycock's Spark parsing system.  PLY might be viewed as cross between
# Spark and the GNU bison utility.
#
# The current implementation is only somewhat object-oriented. The
# LR parser itself is defined in terms of an object (which allows multiple
# parsers to co-exist).  However, most of the variables used during table
# construction are defined in terms of global variables.  Users shouldn't
# notice unless they are trying to define multiple parsers at the same
# time using threads (in which case they should have their head examined).
#
# This implementation supports both SLR and LALR(1) parsing.  LALR(1)
# support was originally implemented by Elias Ioup (ezioup@alumni.uchicago.edu),
# using the algorithm found in Aho, Sethi, and Ullman "Compilers: Principles,
# Techniques, and Tools" (The Dragon Book).  LALR(1) has since been replaced
# by the more efficient DeRemer and Pennello algorithm.
#
# :::::::: WARNING :::::::
#
# Construction of LR parsing tables is fairly complicated and expensive.
# To make this module run fast, a *LOT* of work has been put into
# optimization---often at the expensive of readability and what might
# consider to be good Python "coding style."   Modify the code at your
# own risk!
# ----------------------------------------------------------------------------

import re
import types
import sys
import os.path
import inspect
import base64
import warnings

__version__    = '3.8'
__tabversion__ = '3.8'

#-----------------------------------------------------------------------------
#                     === User configurable parameters ===
#
# Change these to modify the default behavior of yacc (if you wish)
#-----------------------------------------------------------------------------

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
tab_module  = 'parsetab'       # Default name of the table module
default_lr  = 'LALR'           # Default LR table generation method

error_count = 3                # Number of symbols that must be shifted to leave recovery mode

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

# String type-checking compatibility
if sys.version_info[0] < 3:
    string_types = basestring
else:
    string_types = str

MAXINT = sys.maxsize

# 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):
        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 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):
        return self

def __call__(self, *args, **kwargs):
        return self

# Exception raised for yacc-related errors
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 len(repr_str) > resultlimit:
        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 len(repr_str) < 16:
        return repr_str
    else:
        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

_errok = None
_token = None
_restart = None
_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):
        ...
        # Use parser.errok(), parser.token(), parser.restart()
        ...

parser = yacc.yacc()
'''

def errok():
    warnings.warn(_warnmsg)
    return _errok()

def restart():
    warnings.warn(_warnmsg)
    return _restart()

def token():
    warnings.warn(_warnmsg)
    return _token()

# Utility function to call the p_error() function with some deprecation hacks
def call_errorfunc(errorfunc, token, parser):
    global _errok, _token, _restart
    _errok = parser.errok
    _token = parser.token
    _restart = parser.restart
    r = errorfunc(token)
    try:
        del _errok, _token, _restart
    except NameError:
        pass
    return r

#-----------------------------------------------------------------------------
#                        ===  LR Parsing Engine ===
#
# The following classes are used for the LR parser itself.  These are not
# used during table construction and are independent of the actual LR
# table generation algorithm
#-----------------------------------------------------------------------------

# This class is used to hold non-terminal grammar symbols during parsing.
# It normally has the following attributes set:
#        .type       = Grammar symbol type
#        .value      = Symbol value
#        .lineno     = Starting line number
#        .endlineno  = Ending line number (optional, set automatically)
#        .lexpos     = Starting lex position
#        .endlexpos  = Ending lex position (optional, set automatically)

class YaccSymbol:
    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
# .value attribute of the underlying YaccSymbol object.
# The lineno() method returns the line number of a given
# item (or 0 if not defined).   The linespan() method returns
# a tuple of (startline,endline) representing the range of lines
# for a symbol.  The lexspan() method returns a tuple (lexpos,endlexpos)
# representing the range of positional information for a symbol.

class YaccProduction:
    def __init__(self, s, stack=None):
        self.slice = s
        self.stack = stack
        self.lexer = None
        self.parser = None

def __getitem__(self, n):
        if isinstance(n, slice):
            return [s.value for s in self.slice[n]]
        elif n >= 0:
            return self.slice[n].value
        else:
            return self.stack[n].value

def __setitem__(self, n, v):
        self.slice[n].value = v

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 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 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 error(self):
        raise SyntaxError

# -----------------------------------------------------------------------------
#                               == LRParser ==
#
# The LR Parsing engine.
# -----------------------------------------------------------------------------

class LRParser:
    def __init__(self, lrtab, errorf):
        self.productions = lrtab.lr_productions
        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 = True

def restart(self):
        del self.statestack[:]
        del self.symstack[:]
        sym = YaccSymbol()
        sym.type = '$end'
        self.symstack.append(sym)
        self.statestack.append(0)

# 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):
                debug = PlyLogger(sys.stderr)
            return self.parsedebug(input, lexer, debug, tracking, tokenfunc)
        elif tracking:
            return self.parseopt(input, lexer, debug, tracking, tokenfunc)
        else:
            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.   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
    #      #--! 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:
            from . import lex
            lexer = lex.lexer

# Set up the lexer and parser objects on pslice
        pslice.lexer = lexer
        pslice.parser = self

# If input was supplied, pass to lexer
        if input is not None:
            lexer.input(input)

if tokenfunc is None:
            # Tokenize function
            get_token = lexer.token
        else:
            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
        self.statestack = statestack
        symstack   = []                # Stack of grammar symbols
        self.symstack = symstack

pslice.stack = symstack         # Put in the production
        errtoken   = None               # Err token

# The start state is assumed to be (0,$end)

statestack.append(0)
        sym = YaccSymbol()
        sym.type = '$end'
        symstack.append(sym)
        state = 0
        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('State  : %s', state)
            #--! DEBUG

if state not in defaulted_states:
                if not lookahead:
                    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('Stack  : %s',
                        ('%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

symstack.append(lookahead)
                    lookahead = None

# Decrease error count on successful shift
                    if errorcount:
                        errorcount -= 1
                    continue

if t < 0:
                    # reduce a symbol on the stack, emit a production
                    p = prod[-t]
                    pname = p.name
                    plen  = p.len

# Get production function
                    sym = YaccSymbol()
                    sym.type = pname       # Production name
                    sym.value = None

#--! 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:]])+']',
                                   goto[statestack[-1-plen]][pname])
                    else:
                        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
                        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

# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
                        # 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
                            symstack.append(sym)
                            state = goto[statestack[-1]][pname]
                            statestack.append(state)
                        except SyntaxError:
                            # If an error was set. Enter error recovery state
                            lookaheadstack.append(lookahead)
                            symstack.pop()
                            statestack.pop()
                            state = statestack[-1]
                            sym.type = 'error'
                            lookahead = sym
                            errorcount = error_count
                            self.errorok = False
                        continue
                        # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

else:

#--! TRACKING
                        if tracking:
                            sym.lineno = lexer.lineno
                            sym.lexpos = lexer.lexpos
                        #--! TRACKING

targ = [sym]

# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
                        # The code enclosed in this section is duplicated
                        # above 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
                            p.callable(pslice)
                            #--! DEBUG
                            debug.info('Result : %s', format_result(pslice[0]))
                            #--! DEBUG
                            symstack.append(sym)
                            state = goto[statestack[-1]][pname]
                            statestack.append(state)
                        except SyntaxError:
                            # If an error was set. Enter error recovery state
                            lookaheadstack.append(lookahead)
                            symstack.pop()
                            statestack.pop()
                            state = statestack[-1]
                            sym.type = 'error'
                            lookahead = sym
                            errorcount = error_count
                            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
                    return result

if t is None:

#--! DEBUG
                debug.error('Error  : %s',
                            ('%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
                # the tokenstack and replace it with an 'error' token.
                # If there are any synchronization rules, they may
                # catch it.
                #
                # In addition to pushing the error token, we call call
                # the user defined p_error() function if this is the
                # first syntax error.  This function is only called if
                # errorcount == 0.
                if errorcount == 0 or self.errorok:
                    errorcount = error_count
                    self.errorok = False
                    errtoken = lookahead
                    if errtoken.type == '$end':
                        errtoken = None               # End of file!
                    if self.errorfunc:
                        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
                            # returned token is the next lookahead
                            lookahead = tok
                            errtoken = None
                            continue
                    else:
                        if errtoken:
                            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))
                            else:
                                sys.stderr.write('yacc: Syntax error, token=%s' % errtoken.type)
                        else:
                            sys.stderr.write('yacc: Parse error in input. EOF\n')
                            return

else:
                    errorcount = error_count

# case 1:  the statestack only has 1 entry on it.  If we're in this state, the
                # 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':
                    lookahead = None
                    errtoken = None
                    state = 0
                    # Nuke the pushback stack
                    del lookaheadstack[:]
                    continue

# case 2: the statestack has a couple of entries on it, but we're
                # 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':
                    # Whoa. We're really hosed here. Bail out
                    return

if lookahead.type != 'error':
                    sym = symstack[-1]
                    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)
                        #--! 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 = 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]

continue

# Call an error function here
            raise RuntimeError('yacc: internal parser error!!!\n')

#--! parsedebug-end

# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    # parseopt().
    #
    # 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

# If no lexer was given, we will try to use the lex module
        if not lexer:
            from . import lex
            lexer = lex.lexer

# Set up the lexer and parser objects on pslice
        pslice.lexer = lexer
        pslice.parser = self

# If input was supplied, pass to lexer
        if input is not None:
            lexer.input(input)

if tokenfunc is None:
            # Tokenize function
            get_token = lexer.token
        else:
            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
        self.statestack = statestack
        symstack   = []                # Stack of grammar symbols
        self.symstack = symstack

pslice.stack = symstack         # Put in the production
        errtoken   = None               # Err token

# The start state is assumed to be (0,$end)

# Check the action table
                ltype = lookahead.type
                t = actions[state].get(ltype)
            else:
                t = defaulted_states[state]

if t is not None:
                if t > 0:
                    # shift a symbol on the stack
                    statestack.append(t)
                    state = t

symstack.append(lookahead)
                    lookahead = None

# Decrease error count on successful shift
                    if errorcount:
                        errorcount -= 1
                    continue

if t < 0:
                    # reduce a symbol on the stack, emit a production
                    p = prod[-t]
                    pname = p.name
                    plen  = p.len

# Get production function
                    sym = YaccSymbol()
                    sym.type = pname       # Production name
                    sym.value = None

if plen:
                        targ = symstack[-plen-1:]
                        targ[0] = sym

pslice.slice = targ

try:
                            # Call the grammar rule with our special slice object
                            del symstack[-plen:]
                            del statestack[-plen:]
                            p.callable(pslice)
                            symstack.append(sym)
                            state = goto[statestack[-1]][pname]
                            statestack.append(state)
                        except SyntaxError:
                            # If an error was set. Enter error recovery state
                            lookaheadstack.append(lookahead)
                            symstack.pop()
                            statestack.pop()
                            state = statestack[-1]
                            sym.type = 'error'
                            lookahead = sym
                            errorcount = error_count
                            self.errorok = False
                        continue
                        # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

else:

#--! TRACKING
                        if tracking:
                            sym.lineno = lexer.lineno
                            sym.lexpos = lexer.lexpos
                        #--! TRACKING

targ = [sym]

pslice.slice = targ

try:
                            # Call the grammar rule with our special slice object
                            p.callable(pslice)
                            symstack.append(sym)
                            state = goto[statestack[-1]][pname]
                            statestack.append(state)
                        except SyntaxError:
                            # If an error was set. Enter error recovery state
                            lookaheadstack.append(lookahead)
                            symstack.pop()
                            statestack.pop()
                            state = statestack[-1]
                            sym.type = 'error'
                            lookahead = sym
                            errorcount = error_count
                            self.errorok = False
                        continue
                        # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

if t == 0:
                    n = symstack[-1]
                    result = getattr(n, 'value', None)
                    return result

if t is None:

else:
                    errorcount = error_count

# case 2: the statestack has a couple of entries on it, but we're
                # 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':
                    # Whoa. We're really hosed here. Bail out
                    return

# Create the error symbol for the first time and make it the new lookahead symbol
                    t = YaccSymbol()
                    t.type = 'error'

continue

# Call an error function here
            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. 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=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:
            from . import lex
            lexer = lex.lexer

# Set up the lexer and parser objects on pslice
        pslice.lexer = lexer
        pslice.parser = self

# If input was supplied, pass to lexer
        if input is not None:
            lexer.input(input)

if tokenfunc is None:
            # Tokenize function
            get_token = lexer.token
        else:
            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
        self.statestack = statestack
        symstack   = []                # Stack of grammar symbols
        self.symstack = symstack

pslice.stack = symstack         # Put in the production
        errtoken   = None               # Err token

# The start state is assumed to be (0,$end)

# Check the action table
                ltype = lookahead.type
                t = actions[state].get(ltype)
            else:
                t = defaulted_states[state]

if t is not None:
                if t > 0:
                    # shift a symbol on the stack
                    statestack.append(t)
                    state = t

symstack.append(lookahead)
                    lookahead = None

# Decrease error count on successful shift
                    if errorcount:
                        errorcount -= 1
                    continue

if t < 0:
                    # reduce a symbol on the stack, emit a production
                    p = prod[-t]
                    pname = p.name
                    plen  = p.len

# Get production function
                    sym = YaccSymbol()
                    sym.type = pname       # Production name
                    sym.value = None

if plen:
                        targ = symstack[-plen-1:]
                        targ[0] = sym

pslice.slice = targ

else:

targ = [sym]

pslice.slice = targ

if t == 0:
                    n = symstack[-1]
                    result = getattr(n, 'value', None)
                    return result

if t is None:

else:
                    errorcount = error_count

# case 2: the statestack has a couple of entries on it, but we're
                # 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':
                    # Whoa. We're really hosed here. Bail out
                    return

if lookahead.type != 'error':
                    sym = symstack[-1]
                    if sym.type == 'error':
                        # Hmmm. Error is on top of stack, we'll just nuke input
                        # 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'

continue

# Call an error function here
            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.
# -----------------------------------------------------------------------------

# regex matching identifiers
_is_identifier = re.compile(r'^[a-zA-Z0-9_-]+$')

# -----------------------------------------------------------------------------
# class Production:
#
# 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
#
# Here are the basic attributes defined on all productions
#
#       name     - Name of the production.  For example 'expr'
#       prod     - A list of symbols on the right side ['expr','PLUS','term']
#       prec     - Production precedence level
#       number   - Production number.
#       func     - Function that executes on reduce
#       file     - File where production function is defined
#       lineno   - Line number where production function is defined
#
# The following attributes are defined or optional.
#
#       len       - Length of the production (number of symbols on right hand side)
#       usyms     - Set of unique symbols found in the production
# -----------------------------------------------------------------------------

class Production(object):
    reduced = 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
        self.func     = func
        self.callable = None
        self.file     = file
        self.line     = line
        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 = []
        for s in self.prod:
            if s not in self.usyms:
                self.usyms.append(s)

# List of all LR items for the production
        self.lr_items = []
        self.lr_next = None

# Create a string representation
        if self.prod:
            self.str = '%s -> %s' % (self.name, ' '.join(self.prod))
        else:
            self.str = '%s -> <empty>' % self.name

def __str__(self):
        return self.str

def __repr__(self):
        return 'Production(' + str(self) + ')'

def __len__(self):
        return len(self.prod)

def __nonzero__(self):
        return 1

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.
        try:
            p.lr_after = Prodnames[p.prod[n+1]]
        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):
        if self.func:
            self.callable = pdict[self.func]

# This class serves as a minimal standin for Production objects when
# reading table data from files.   It only contains information
# actually used by the LR parsing engine, plus some additional
# debugging information.
class MiniProduction(object):
    def __init__(self, str, name, len, func, file, line):
        self.name     = name
        self.len      = len
        self.func     = func
        self.callable = None
        self.file     = file
        self.line     = line
        self.str      = str

def __str__(self):
        return self.str

def __repr__(self):
        return 'MiniProduction(%s)' % self.str

# Bind the production function name to a callable
    def bind(self, pdict):
        if self.func:
            self.callable = pdict[self.func]

# -----------------------------------------------------------------------------
# class LRItem
#
# This class represents a specific stage of parsing a production rule.  For
# example:
#
#       expr : expr . PLUS term
#
# In the above, the "." represents the current location of the parse.  Here
# basic attributes:
#
#       name       - Name of the production.  For example 'expr'
#       prod       - A list of symbols on the right side ['expr','.', 'PLUS','term']
#       number     - Production number.
#
#       lr_next      Next LR item. Example, if we are ' expr -> expr . PLUS term'
#                    then lr_next refers to 'expr -> expr PLUS . term'
#       lr_index   - LR item index (location of the ".") in the prod list.
#       lookaheads - LALR lookahead symbols for this item
#       len        - Length of the production (number of symbols on right hand side)
#       lr_after    - List of all productions that immediately follow
#       lr_before   - Grammar symbol immediately before
# -----------------------------------------------------------------------------

class LRItem(object):
    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.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))
        else:
            s = '%s -> <empty>' % self.name
        return s

def __repr__(self):
        return 'LRItem(' + str(self) + ')'

# -----------------------------------------------------------------------------
# rightmost_terminal()
#
# Return the rightmost terminal from a list of symbols.  Used in add_production()
# -----------------------------------------------------------------------------
def rightmost_terminal(symbols, terminals):
    i = len(symbols) - 1
    while i >= 0:
        if symbols[i] in terminals:
            return symbols[i]
        i -= 1
    return None

# -----------------------------------------------------------------------------
#                           === GRAMMAR CLASS ===
#
# The following class represents the contents of the specified grammar along
# with various computed properties such as first sets, follow sets, LR items, etc.
# This data is used for critical parts of the table generation process later.
# -----------------------------------------------------------------------------

class GrammarError(YaccError):
    pass

class Grammar(object):
    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
                                    # productions of that nonterminal.

self.Prodmap      = {}      # A dictionary that is only used to detect duplicate
                                    # productions.

self.Terminals    = {}      # A dictionary mapping the names of terminal symbols to a
                                    # list of the rules where they are used.

for term in terminals:
            self.Terminals[term] = []

self.Terminals['error'] = []

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.Follow       = {}      # A dictionary of precomputed FOLLOW(x) symbols

self.Precedence   = {}      # Precedence rules for each terminal. Contains tuples of the
                                    # form ('right',level) or ('nonassoc', level) or ('left',level)

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.

self.Start = None           # Starting symbol for the grammar

def __len__(self):
        return len(self.Productions)

def __getitem__(self, index):
        return self.Productions[index]

# -----------------------------------------------------------------------------
    # set_precedence()
    #
    # Sets the precedence for a given terminal. assoc is the associativity such as
    # 'left','right', or 'nonassoc'.  level is a numeric level.
    #
    # -----------------------------------------------------------------------------

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("Associativity must be one of 'left','right', or 'nonassoc'")
        self.Precedence[term] = (assoc, level)

# -----------------------------------------------------------------------------
    # add_production()
    #
    # Given an action function, this function assembles a production rule and
    # computes its precedence level.
    #
    # The production rule is supplied as a list of symbols.   For example,
    # a rule such as 'expr : expr PLUS term' has a production name of 'expr' and
    # symbols ['expr','PLUS','term'].
    #
    # Precedence is determined by the precedence of the right-most non-terminal
    # or the precedence of a terminal specified by %prec.
    #
    # A variety of error checks are performed to make sure production symbols
    # are valid and that %prec is used correctly.
    # -----------------------------------------------------------------------------

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))
        if prodname == 'error':
            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))

# 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 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))

# Determine the precedence level
        if '%prec' in syms:
            if syms[-1] == '%prec':
                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))
            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))
            else:
                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))

# See if the rule is already in the rulemap
        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))

# From this point on, everything is valid.  Create a new Production instance
        pnumber  = len(self.Productions)
        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 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)
        self.Productions.append(p)
        self.Prodmap[map] = p

# Add to the global productions list
        try:
            self.Prodnames[prodname].append(p)
        except KeyError:
            self.Prodnames[prodname] = [p]

# -----------------------------------------------------------------------------
    # set_start()
    #
    # 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):
        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])
        self.Nonterminals[start].append(0)
        self.Start = start

# -----------------------------------------------------------------------------
    # find_unreachable()
    #
    # Find all of the nonterminal symbols that can't be reached from the starting
    # symbol.  Returns a list of nonterminals that can't be reached.
    # -----------------------------------------------------------------------------

def find_unreachable(self):

# Mark all symbols that are reachable from a symbol s
        def mark_reachable_from(s):
            if s in reachable:
                return
            reachable.add(s)
            for p in self.Prodnames.get(s, []):
                for r in p.prod:
                    mark_reachable_from(r)

reachable = set()
        mark_reachable_from(self.Productions[0].prod[0])
        return [s for s in self.Nonterminals if s not in reachable]

# -----------------------------------------------------------------------------
    # infinite_cycles()
    #
    # This function looks at the various parsing rules and tries to detect
    # infinite recursion cycles (grammar rules where there is no possible way
    # to derive a string of only terminals).
    # -----------------------------------------------------------------------------

def infinite_cycles(self):
        terminates = {}

# Terminals:
        for t in self.Terminals:
            terminates[t] = True

terminates['$end'] = True

# Nonterminals:

# Initialize to false:
        for n in self.Nonterminals:
            terminates[n] = False

# Then propagate termination until no change:
        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.
                    for s in p.prod:
                        if not terminates[s]:
                            # The symbol s does not terminate,
                            # so production p does not terminate.
                            p_terminates = False
                            break
                    else:
                        # didn't break from the loop,
                        # so every symbol s terminates
                        # so production p terminates.
                        p_terminates = True

if p_terminates:
                        # symbol n terminates!
                        if not terminates[n]:
                            terminates[n] = True
                            some_change = True
                        # Don't need to consider any more productions for this n.
                        break

if not some_change:
                break

infinite = []
        for (s, term) in terminates.items():
            if not term:
                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
                else:
                    infinite.append(s)

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.
    # -----------------------------------------------------------------------------
    def undefined_symbols(self):
        result = []
        for p in self.Productions:
            if not p:
                continue

for s in p.prod:
                if s not in self.Prodnames and s not in self.Terminals and s != 'error':
                    result.append((s, p))
        return result

# -----------------------------------------------------------------------------
    # unused_terminals()
    #
    # Find all terminals that were defined, but not used by the grammar.  Returns
    # a list of all symbols.
    # -----------------------------------------------------------------------------
    def unused_terminals(self):
        unused_tok = []
        for s, v in self.Terminals.items():
            if s != 'error' and not v:
                unused_tok.append(s)

return unused_tok

# ------------------------------------------------------------------------------
    # unused_rules()
    #
    # Find all grammar rules that were defined,  but not used (maybe not reachable)
    # Returns a list of productions.
    # ------------------------------------------------------------------------------

def unused_rules(self):
        unused_prod = []
        for s, v in self.Nonterminals.items():
            if not v:
                p = self.Prodnames[s][0]
                unused_prod.append(p)
        return unused_prod

# -----------------------------------------------------------------------------
    # unused_precedence()
    #
    # 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.
    # -----------------------------------------------------------------------------

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]))

return unused

# -------------------------------------------------------------------------
    # _first()
    #
    # Compute the value of FIRST1(beta) where beta is a tuple of symbols.
    #
    # 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):

# We are computing First(x1,x2,x3,...,xn)
        result = []
        for x in beta:
            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 = True
                else:
                    if f not in result:
                        result.append(f)

if x_produces_empty:
                # We have to consider the next x in beta,
                # i.e. stay in the loop.
                pass
            else:
                # We don't have to consider any further symbols in beta.
                break
        else:
            # There was no 'break' from the loop,
            # so x_produces_empty was true for all x in beta,
            # so beta produces empty as well.
            result.append('<empty>')

return result

# -------------------------------------------------------------------------
    # compute_first()
    #
    # Compute the value of FIRST1(X) for all symbols
    # -------------------------------------------------------------------------
    def compute_first(self):
        if self.First:
            return self.First

# Terminals:
        for t in self.Terminals:
            self.First[t] = [t]

self.First['$end'] = ['$end']

# Nonterminals:

# Initialize to the empty set:
        for n in self.Nonterminals:
            self.First[n] = []

# Then propagate symbols until no change:
        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 = True
            if not some_change:
                break

return self.First

# ---------------------------------------------------------------------
    # compute_follow()
    #
    # Computes all of the follow sets for every non-terminal symbol.  The
    # 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):
        # If already computed, return the result
        if self.Follow:
            return self.Follow

# If first sets not computed yet, do that first.
        if not self.First:
            self.compute_first()

# Add '$end' to the follow list of the start symbol
        for k in self.Nonterminals:
            self.Follow[k] = []

if not start:
            start = self.Productions[1].name

self.Follow[start] = ['$end']

while True:
            didadd = False
            for p in self.Productions[1:]:
                # Here is the production set
                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 = False
                        for f in fst:
                            if f != '<empty>' and f not in self.Follow[B]:
                                self.Follow[B].append(f)
                                didadd = True
                            if f == '<empty>':
                                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 = True
            if not didadd:
                break
        return self.Follow

# -----------------------------------------------------------------------------
    # build_lritems()
    #
    # This function walks the list of productions and builds a complete set of the
    # LR items.  The LR items are stored in two ways:  First, they are uniquely
    # numbered and placed in the list _lritems.  Second, a linked list of LR items
    # is built for each production.  For example:
    #
    #   E -> E PLUS E
    #
    # Creates the list
    #
    #  [E -> . E PLUS E, E -> E . PLUS E, E -> E PLUS . E, E -> E PLUS E . ]
    # -----------------------------------------------------------------------------

def build_lritems(self):
        for p in self.Productions:
            lastlri = p
            i = 0
            lr_items = []
            while True:
                if i > len(p):
                    lri = None
                else:
                    lri = LRItem(p, i)
                    # Precompute the list of productions immediately following
                    try:
                        lri.lr_after = self.Prodnames[lri.prod[i+1]]
                    except (IndexError, KeyError):
                        lri.lr_after = []
                    try:
                        lri.lr_before = lri.prod[i-1]
                    except IndexError:
                        lri.lr_before = None

lastlri.lr_next = lri
                if not lri:
                    break
                lr_items.append(lri)
                lastlri = lri
                i += 1
            p.lr_items = lr_items

# -----------------------------------------------------------------------------
#                            == Class LRTable ==
#
# 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 LRTable(object):
    def __init__(self):
        self.lr_action = None
        self.lr_goto = None
        self.lr_productions = None
        self.lr_method = None

def read_table(self, module):
        if isinstance(module, types.ModuleType):
            parsetab = module
        else:
            exec('import %s' % module)
            parsetab = sys.modules[module]

if parsetab._tabversion != __tabversion__:
            raise VersionError('yacc table file version is out of date')

self.lr_action = parsetab._lr_action
        self.lr_goto = parsetab._lr_goto

self.lr_productions = []
        for p in parsetab._lr_productions:
            self.lr_productions.append(MiniProduction(*p))

self.lr_method = parsetab._lr_method
        return parsetab._lr_signature

def read_pickle(self, filename):
        try:
            import cPickle as pickle
        except ImportError:
            import pickle
        
        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')
        self.lr_method = pickle.load(in_f)
        signature      = pickle.load(in_f)
        self.lr_action = pickle.load(in_f)
        self.lr_goto   = pickle.load(in_f)
        productions    = pickle.load(in_f)

self.lr_productions = []
        for p in productions:
            self.lr_productions.append(MiniProduction(*p))

in_f.close()
        return signature

# Bind all production function names to callable objects in 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
# a grammar.
# -----------------------------------------------------------------------------

# -----------------------------------------------------------------------------
# digraph()
# traverse()
#
# The following two functions are used to compute set valued functions
# of the form:
#
#     F(x) = F'(x) U U{F(y) | x R y}
#
# This is used to compute the values of Read() sets as well as FOLLOW sets
# in LALR(1) generation.
#
# Inputs:  X    - An input set
#          R    - A relation
#          FP   - Set-valued function
# ------------------------------------------------------------------------------

def digraph(X, R, FP):
    N = {}
    for x in X:
        N[x] = 0
    stack = []
    F = {}
    for x in X:
        if N[x] == 0:
            traverse(x, N, stack, F, X, R, FP)
    return F

def traverse(x, N, stack, F, X, R, FP):
    stack.append(x)
    d = len(stack)
    N[x] = d
    F[x] = FP(x)             # F(X) <- F'(x)

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)
    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()

class LALRError(YaccError):
    pass

# -----------------------------------------------------------------------------
#                             == LRGeneratedTable ==
#
# This class implements the LR table generation algorithm.  There are no
# public methods except for write()
# -----------------------------------------------------------------------------

class LRGeneratedTable(LRTable):
    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

# Set up the logger
        if not log:
            log = NullLogger()
        self.log = log

# Internal attributes
        self.lr_action     = {}        # Action table
        self.lr_goto       = {}        # Goto table
        self.lr_productions  = grammar.Productions    # Copy of grammar Production array
        self.lr_goto_cache = {}        # Cache of computed gotos
        self.lr0_cidhash   = {}        # Cache of closures

self._add_count    = 0         # Internal counter used to detect cycles

# Diagonistic information filled in by the table generator
        self.sr_conflict   = 0
        self.rr_conflict   = 0
        self.conflicts     = []        # List of conflicts

self.sr_conflicts  = []
        self.rr_conflicts  = []

# Build the tables
        self.grammar.build_lritems()
        self.grammar.compute_first()
        self.grammar.compute_follow()
        self.lr_parse_table()

# Compute the LR(0) closure operation on I, where I is a set of LR(0) items.

def lr0_closure(self, I):
        self._add_count += 1

# Add everything in I to J
        J = I[:]
        didadd = True
        while didadd:
            didadd = False
            for j in J:
                for x in j.lr_after:
                    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 = True

return J

# Compute the LR(0) goto function goto(I,X) where I is a set
    # of LR(0) items and X is a grammar symbol.   This function is written
    # in a way that guarantees uniqueness of the generated goto sets
    # (i.e. the same goto set will never be returned as two different Python
    # objects).  With uniqueness, we can later do fast set comparisons using
    # id(obj) instead of element-wise comparison.

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

# 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 = {}
            self.lr_goto_cache[x] = s

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 = {}
                    s[id(n)] = s1
                gs.append(n)
                s = s1
        g = s.get('$end')
        if not g:
            if gs:
                g = self.lr0_closure(gs)
                s['$end'] = g
            else:
                s['$end'] = gs
        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])]
        i = 0
        for I in C:
            self.lr0_cidhash[id(I)] = i
            i += 1

# Loop over the items in C and each grammar symbols
        i = 0
        while i < len(C):
            I = C[i]
            i += 1

# Collect all of the symbols that could possibly be in the goto(I,X) sets
            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 or id(g) in self.lr0_cidhash:
                    continue
                self.lr0_cidhash[id(g)] = len(C)
                C.append(g)

return C

# -----------------------------------------------------------------------------
    #                       ==== LALR(1) Parsing ====
    #
    # LALR(1) parsing is almost exactly the same as SLR except that instead of
    # relying upon Follow() sets when performing reductions, a more selective
    # lookahead set that incorporates the state of the LR(0) machine is utilized.
    # Thus, we mainly just have to focus on calculating the lookahead sets.
    #
    # The method used here is due to DeRemer and Pennelo (1982).
    #
    # DeRemer, F. L., and T. J. Pennelo: "Efficient Computation of LALR(1)
    #     Lookahead Sets", ACM Transactions on Programming Languages and Systems,
    #     Vol. 4, No. 4, Oct. 1982, pp. 615-649
    #
    # Further details can also be found in:
    #
    #  J. Tremblay and P. Sorenson, "The Theory and Practice of Compiler Writing",
    #      McGraw-Hill Book Company, (1985).
    #
    # -----------------------------------------------------------------------------

# -----------------------------------------------------------------------------
    # compute_nullable_nonterminals()
    #
    # Creates a dictionary containing all of the non-terminals that might produce
    # an empty production.
    # -----------------------------------------------------------------------------

def compute_nullable_nonterminals(self):
        nullable = set()
        num_nullable = 0
        while True:
            for p in self.grammar.Productions[1:]:
                if p.len == 0:
                    nullable.add(p.name)
                    continue
                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

# -----------------------------------------------------------------------------
    # find_nonterminal_trans(C)
    #
    # Given a set of LR(0) items, this functions finds all of the non-terminal
    # transitions.    These are transitions in which a dot appears immediately before
    # a non-terminal.   Returns a list of tuples of the form (state,N) where state
    # is the state number and N is the nonterminal symbol.
    #
    # The input C is the set of LR(0) items.
    # -----------------------------------------------------------------------------

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()
    #
    # Computes the DR(p,A) relationships for non-terminal transitions.  The input
    # is a tuple (state,N) where state is a number and N is a nonterminal symbol.
    #
    # Returns a list of terminals.
    # -----------------------------------------------------------------------------

def dr_relation(self, C, trans, nullable):
        dr_set = {}
        state, N = trans
        terms = []

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)

# This extra bit is to handle the start state
        if state == 0 and N == self.grammar.Productions[0].prod[0]:
            terms.append('$end')

return terms

# -----------------------------------------------------------------------------
    # reads_relation()
    #
    # Computes the READS() relation (p,A) READS (t,C).
    # -----------------------------------------------------------------------------

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)
        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))

return rel

# -----------------------------------------------------------------------------
    # compute_lookback_includes()
    #
    # Determines the lookback and includes relations
    #
    # LOOKBACK:
    #
    # This relation is determined by running the LR(0) state machine forward.
    # For example, starting with a production "N : . A B C", we run it forward
    # to obtain "N : A B C ."   We then build a relationship between this final
    # state and the starting state.   These relationships are stored in a dictionary
    # lookdict.
    #
    # INCLUDES:
    #
    # Computes the INCLUDE() relation (p,A) INCLUDES (p',B).
    #
    # This relation is used to determine non-terminal transitions that occur
    # inside of other non-terminal transition states.   (p,A) INCLUDES (p', B)
    # if the following holds:
    #
    #       B -> LAT, where T -> epsilon and p' -L-> p
    #
    # L is essentially a prefix (which may be empty), T is a suffix that must be
    # able to derive an empty string.  State p' must lead to state p with the string L.
    #
    # -----------------------------------------------------------------------------

def compute_lookback_includes(self, C, trans, nullable):
        lookdict = {}          # Dictionary of lookback relations
        includedict = {}       # Dictionary of include relations

# Make a dictionary of non-terminal transitions
        dtrans = {}
        for t in trans:
            dtrans[t] = 1

# Loop over all transitions and compute lookbacks and includes
        for state, N in trans:
            lookb = []
            includes = []
            for p in C[state]:
                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

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 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))
            for i in includes:
                if i not in includedict:
                    includedict[i] = []
                includedict[i].append((state, N))
            lookdict[(state, N)] = lookb

return lookdict, includedict

# -----------------------------------------------------------------------------
    # compute_read_sets()
    #
    # Given a set of LR(0) items, this function computes the read sets.
    #
    # Inputs:  C        =  Set of LR(0) items
    #          ntrans   = Set of nonterminal transitions
    #          nullable = Set of empty transitions
    #
    # 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)
        return F

# -----------------------------------------------------------------------------
    # compute_follow_sets()
    #
    # Given a set of LR(0) items, a set of non-terminal transitions, a readset,
    # and an include set, this function computes the follow sets
    #
    # Follow(p,A) = Read(p,A) U U {Follow(p',B) | (p,A) INCLUDES (p',B)}
    #
    # Inputs:
    #            ntrans     = Set of nonterminal transitions
    #            readsets   = Readset (previously computed)
    #            inclsets   = Include sets (previously computed)
    #
    # 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

# -----------------------------------------------------------------------------
    # add_lookaheads()
    #
    # Attaches the lookahead symbols to grammar rules.
    #
    # Inputs:    lookbacks         -  Set of lookback relations
    #            followset         -  Computed follow set
    #
    # This function directly attaches the lookaheads to productions contained
    # in the lookbacks set
    # -----------------------------------------------------------------------------

def add_lookaheads(self, lookbacks, followset):
        for trans, lb in lookbacks.items():
            # Loop over productions in lookback
            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()
    #
    # This function does all of the work of adding lookahead information for use
    # with LALR parsing
    # -----------------------------------------------------------------------------

def add_lalr_lookaheads(self, C):
        # Determine all of the nullable nonterminals
        nullable = self.compute_nullable_nonterminals()

# Find all non-terminal transitions
        trans = self.find_nonterminal_transitions(C)

# Compute read sets
        readsets = self.compute_read_sets(C, trans, nullable)

# Compute lookback/includes relations
        lookd, included = self.compute_lookback_includes(C, trans, nullable)

# Compute LALR FOLLOW sets
        followsets = self.compute_follow_sets(trans, readsets, included)

# Add all of the lookaheads
        self.add_lookaheads(lookd, followsets)

# -----------------------------------------------------------------------------
    # lr_parse_table()
    #
    # This function constructs the parse tables for SLR or LALR
    # -----------------------------------------------------------------------------
    def lr_parse_table(self):
        Productions = self.grammar.Productions
        Precedence  = self.grammar.Precedence
        goto   = self.lr_goto         # Goto array
        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)

# Step 1: Construct C = { I0, I1, ... IN}, collection of LR(0) items
        # This determines the number of states

C = self.lr0_items()

if self.lr_method == 'LALR':
            self.add_lalr_lookaheads(C)

# Build the parser table, state by state
        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('')
            for p in I:
                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
                        else:
                            # We are at the end of a production.  Reduce!
                            if self.lr_method == 'LALR':
                                laheads = p.lookaheads[st]
                            else:
                                laheads = self.grammar.Follow[p.name]
                            for a in laheads:
                                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
                                    if r > 0:
                                        # 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))
                                        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'))
                                            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'))
                                    elif r < 0:
                                        # Reduce/reduce conflict.   In this case, we favor the rule
                                        # that was defined first in the grammar file
                                        oldp = Productions[-r]
                                        pp = Productions[p.number]
                                        if oldp.line > pp.line:
                                            st_action[a] = -p.number
                                            st_actionp[a] = p
                                            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])
                                    else:
                                        raise LALRError('Unknown conflict in state %d' % st)
                                else:
                                    st_action[a] = -p.number
                                    st_actionp[a] = p
                                    Productions[p.number].reduced += 1
                    else:
                        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)
                            if j >= 0:
                                # We are in a shift state
                                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)
                                    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))
                                        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'))
                                        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'))

else:
                                        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:
                if a in st_action:
                    if p is st_actionp[a]:
                        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:
                if a in st_action:
                    if p is not st_actionp[a]:
                        if not (a, m) in _actprint:
                            log.debug('  ! %-15s [ %s ]', a, m)
                            not_used = 1
                            _actprint[(a, m)] = 1
            if not_used:
                log.debug('')

# Construct the goto table for this state

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)
                if j >= 0:
                    st_goto[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, 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.write('''
# %s
# This file is automatically generated. Do not edit.
_tabversion = %r

_lr_method = %r

_lr_signature = %r
    ''' % (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)
                    for i in v[0]:
                        f.write('%r,' % i)
                    f.write('],[')
                    for i in v[1]:
                        f.write('%r,' % i)

f.write(']),')
                f.write('}\n')

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] = {}
      _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')

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)
                    for i in v[0]:
                        f.write('%r,' % i)
                    f.write('],[')
                    for i in v[1]:
                        f.write('%r,' % i)

f.write(']),')
                f.write('}\n')

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] = {}
       _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')

# Write production table
            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, 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.close()

except IOError as e:
            raise

# -----------------------------------------------------------------------------
    # pickle_table()
    #
    # This function pickles the LR parsing tables to a supplied file object
    # -----------------------------------------------------------------------------

def pickle_table(self, filename, signature=''):
        try:
            import cPickle as pickle
        except ImportError:
            import pickle
        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 ===
#
# The following functions and classes are used to implement the PLY
# introspection features followed by the yacc() function itself.
# -----------------------------------------------------------------------------

# -----------------------------------------------------------------------------
# get_caller_module_dict()
#
# This function returns a dictionary containing all of the symbols defined within
# a caller further down the call stack.  This is used to get the environment
# associated with the yacc() call if none was provided.
# -----------------------------------------------------------------------------

def get_caller_module_dict(levels):
    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):
    grammar = []
    # Split the doc string into lines
    pstrings = doc.splitlines()
    lastp = None
    dline = line
    for ps in pstrings:
        dline += 1
        p = ps.split()
        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))
                prodname = lastp
                syms = p[1:]
            else:
                prodname = p[0]
                lastp = prodname
                syms   = p[2:]
                assign = p[1]
                if assign != ':' and assign != '::=':
                    raise SyntaxError("%s:%d: Syntax error. Expected ':'" % (file, dline))

grammar.append((file, dline, prodname, syms))
        except SyntaxError:
            raise
        except Exception:
            raise SyntaxError('%s:%d: Syntax error in rule %r' % (file, dline, ps.strip()))

return grammar

# -----------------------------------------------------------------------------
# ParserReflect()
#
# This class represents information extracted for building a parser including
# start symbol, error function, tokens, precedence list, action functions,
# etc.
# -----------------------------------------------------------------------------
class ParserReflect(object):
    def __init__(self, pdict, log=None):
        self.pdict      = pdict
        self.start      = None
        self.error_func = None
        self.tokens     = None
        self.modules    = set()
        self.grammar    = []
        self.error      = False

if log is None:
            self.log = PlyLogger(sys.stderr)
        else:
            self.log = log

# Get all of the basic information
    def get_all(self):
        self.get_start()
        self.get_error_func()
        self.get_tokens()
        self.get_precedence()
        self.get_pfunctions()

# Validate all of the information
    def validate_all(self):
        self.validate_start()
        self.validate_error_func()
        self.validate_tokens()
        self.validate_precedence()
        self.validate_pfunctions()
        self.validate_modules()
        return self.error

# Compute a signature over the grammar
    def signature(self):
        try:
            from hashlib import md5
        except ImportError:
            from md5 import md5
        try:
            sig = md5()
            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'))
            if self.tokens:
                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):
            pass

digest = base64.b16encode(sig.digest())
        if sys.version_info[0] >= 3:
            digest = digest.decode('latin-1')
        return digest

# -----------------------------------------------------------------------------
    # validate_modules()
    #
    # This method checks to see if there are duplicated p_rulename() functions
    # in the parser module file.  Without this function, it is really easy for
    # users to make mistakes by cutting and pasting code fragments (and it's a real
    # bugger to try and figure out why the resulting parser doesn't work).  Therefore,
    # we just do a little regular expression pattern matching of def statements
    # to try and detect duplicates.
    # -----------------------------------------------------------------------------

def validate_modules(self):
        # Match def p_funcname(
        fre = re.compile(r'\s*def\s+(p_[a-zA-Z_0-9]*)\(')

for module in self.modules:
            lines, linen = inspect.getsourcelines(module)

counthash = {}
            for linen, line in enumerate(lines):
                linen += 1
                m = fre.match(line)
                if m:
                    name = m.group(1)
                    prev = counthash.get(name)
                    if not prev:
                        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)

# Get the start symbol
    def get_start(self):
        self.start = self.pdict.get('start')

# Validate the start symbol
    def validate_start(self):
        if self.start is not None:
            if not isinstance(self.start, string_types):
                self.log.error("'start' must be a string")

# Look for error handler
    def get_error_func(self):
        self.error_func = self.pdict.get('p_error')

# Validate the error function
    def validate_error_func(self):
        if self.error_func:
            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 = True
                return

eline = self.error_func.__code__.co_firstlineno
            efile = self.error_func.__code__.co_filename
            module = inspect.getmodule(self.error_func)
            self.modules.add(module)

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 = True

# Get the tokens map
    def get_tokens(self):
        tokens = self.pdict.get('tokens')
        if not tokens:
            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 = True
            return

if not tokens:
            self.log.error('tokens is empty')
            self.error = True
            return

self.tokens = tokens

# Validate the tokens
    def validate_tokens(self):
        # Validate the tokens.
        if 'error' in self.tokens:
            self.log.error("Illegal token name 'error'. Is a reserved word")
            self.error = True
            return

terminals = set()
        for n in self.tokens:
            if n in terminals:
                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')

# 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 = True
                return
            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 = True
                    return
                assoc = p[0]
                if not isinstance(assoc, string_types):
                    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 = True
                        return
                    preclist.append((term, assoc, level+1))
        self.preclist = preclist

# Get all p_functions from the grammar
    def get_pfunctions(self):
        p_functions = []
        for name, item in self.pdict.items():
            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; 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 = True
            return

for line, module, name, doc in self.pfuncs:
            file = inspect.getsourcefile(module)
            func = self.pdict[name]
            if isinstance(func, types.MethodType):
                reqargs = 2
            else:
                reqargs = 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__)
            else:
                try:
                    parsed_g = parse_grammar(doc, file, line)
                    for g in parsed_g:
                        grammar.append((name, g))
                except SyntaxError as e:
                    self.log.error(str(e))
                    self.error = True

# Looks like a valid grammar rule
                # Mark the file in which defined.
                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
            if n.startswith('p_') and n != 'p_error':
                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

# -----------------------------------------------------------------------------
# yacc(module)
#
# Build a parser
# -----------------------------------------------------------------------------

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):

if tabmodule is None:
        tabmodule = tab_module

# 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

if errorlog is None:
        errorlog = PlyLogger(sys.stderr)

# Get the module dictionary used for the parser
    if 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.get_all()

if pinfo.error:
        raise YaccError('Unable to build parser')

# Check signature against table files (if any)
    signature = pinfo.signature()

# Read the tables
    try:
        lr = LRTable()
        if picklefile:
            read_signature = lr.read_pickle(picklefile)
        else:
            read_signature = lr.read_table(tabmodule)
        if optimize or (read_signature == signature):
            try:
                lr.bind_callables(pinfo.pdict)
                parser = LRParser(lr, pinfo.error_func)
                parse = parser.parse
                return parser
            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 ImportError:
        pass

if debuglog is None:
        if debug:
            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__)

errors = False

# Validate the parser information
    if pinfo.validate_all():
        raise YaccError('Unable to build parser')

if not pinfo.error_func:
        errorlog.warning('no p_error() function is defined')

# Create a grammar object
    grammar = Grammar(pinfo.tokens)

# Set precedence level for terminals
    for term, assoc, level in pinfo.preclist:
        try:
            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 as e:
            errorlog.error('%s', e)
            errors = True

# Set the grammar start symbols
    try:
        if start is None:
            grammar.set_start(pinfo.start)
        else:
            grammar.set_start(start)
    except GrammarError as e:
        errorlog.error(str(e))
        errors = True

if errors:
        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 = True

unused_terminals = grammar.unused_terminals()
    if unused_terminals:
        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)

# 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)

# 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)

if len(unused_terminals) == 1:
        errorlog.warning('There is 1 unused token')
    if len(unused_terminals) > 1:
        errorlog.warning('There are %d unused tokens', len(unused_terminals))

if len(unused_rules) == 1:
        errorlog.warning('There is 1 unused rule')
    if len(unused_rules) > 1:
        errorlog.warning('There are %d unused rules', len(unused_rules))

if debug:
        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('')
        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('')

if check_recursion:
        unreachable = grammar.find_unreachable()
        for u in unreachable:
            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 = 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 = True

if errors:
        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)

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')
        elif num_sr > 1:
            errorlog.warning('%d shift/reduce conflicts', num_sr)

num_rr = len(lr.rr_conflicts)
        if num_rr == 1:
            errorlog.warning('1 reduce/reduce conflict')
        elif num_rr > 1:
            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('')

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 = set()
        for state, rule, rejected in lr.rr_conflicts:
            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.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)
                warned_never.append(rejected)

# Write the table file if requested
    if write_tables:
        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:
        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)

parse = parser.parse
    return parser

cmd: