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James Taylor  committed 07fc5e2

Update pyparsing to latest version (1.5.0)

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  • Parent commits 0fbfac6

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File lib/bx_extras/pyparsing.py

 # module pyparsing.py
 #
-# Copyright (c) 2003-2006  Paul T. McGuire
+# Copyright (c) 2003-2008  Paul T. McGuire
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
 # TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 # SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #
-#  Todo:
-#  - add pprint() - pretty-print output of defined BNF
-#
 #from __future__ import generators
 
 __doc__ = \
 """
 pyparsing module - Classes and methods to define and execute parsing grammars
 
-The pyparsing module is an alternative approach to creating and executing simple grammars, 
+The pyparsing module is an alternative approach to creating and executing simple grammars,
 vs. the traditional lex/yacc approach, or the use of regular expressions.  With pyparsing, you
-don't need to learn a new syntax for defining grammars or matching expressions - the parsing module 
+don't need to learn a new syntax for defining grammars or matching expressions - the parsing module
 provides a library of classes that you use to construct the grammar directly in Python.
 
 Here is a program to parse "Hello, World!" (or any greeting of the form "<salutation>, <addressee>!")::
 
     from pyparsing import Word, alphas
-    
+
     # define grammar of a greeting
-    greet = Word( alphas ) + "," + Word( alphas ) + "!" 
-    
+    greet = Word( alphas ) + "," + Word( alphas ) + "!"
+
     hello = "Hello, World!"
     print hello, "->", greet.parseString( hello )
 
 
     Hello, World! -> ['Hello', ',', 'World', '!']
 
-The Python representation of the grammar is quite readable, owing to the self-explanatory 
+The Python representation of the grammar is quite readable, owing to the self-explanatory
 class names, and the use of '+', '|' and '^' operators.
 
-The parsed results returned from parseString() can be accessed as a nested list, a dictionary, or an 
+The parsed results returned from parseString() can be accessed as a nested list, a dictionary, or an
 object with named attributes.
 
 The pyparsing module handles some of the problems that are typically vexing when writing text parsers:
  - quoted strings
  - embedded comments
 """
-__version__ = "1.4.1"
-__versionTime__ = "06 February 2006 07:10"
+
+__version__ = "1.5.0"
+__versionTime__ = "28 May 2008 10:05"
 __author__ = "Paul McGuire <ptmcg@users.sourceforge.net>"
 
 import string
+from weakref import ref as wkref
 import copy,sys
 import warnings
 import re
+import sre_constants
+import xml.sax.saxutils
 #~ sys.stderr.write( "testing pyparsing module, version %s, %s\n" % (__version__,__versionTime__ ) )
 
-def _ustr(obj):
-    """Drop-in replacement for str(obj) that tries to be Unicode friendly. It first tries
-       str(obj). If that fails with a UnicodeEncodeError, then it tries unicode(obj). It
-       then < returns the unicode object | encodes it with the default encoding | ... >.
-    """
-    try:
-        # If this works, then _ustr(obj) has the same behaviour as str(obj), so
-        # it won't break any existing code.
-        return str(obj)
-        
-    except UnicodeEncodeError, e:
-        # The Python docs (http://docs.python.org/ref/customization.html#l2h-182)
-        # state that "The return value must be a string object". However, does a
-        # unicode object (being a subclass of basestring) count as a "string
-        # object"?
-        # If so, then return a unicode object:
-        return unicode(obj)
-        # Else encode it... but how? There are many choices... :)
-        # Replace unprintables with escape codes?
-        #return unicode(obj).encode(sys.getdefaultencoding(), 'backslashreplace_errors')
-        # Replace unprintables with question marks?
-        #return unicode(obj).encode(sys.getdefaultencoding(), 'replace')
-        # ...
+__all__ = [
+'And', 'CaselessKeyword', 'CaselessLiteral', 'CharsNotIn', 'Combine', 'Dict', 'Each', 'Empty',
+'FollowedBy', 'Forward', 'GoToColumn', 'Group', 'Keyword', 'LineEnd', 'LineStart', 'Literal',
+'MatchFirst', 'NoMatch', 'NotAny', 'OneOrMore', 'OnlyOnce', 'Optional', 'Or',
+'ParseBaseException', 'ParseElementEnhance', 'ParseException', 'ParseExpression', 'ParseFatalException',
+'ParseResults', 'ParseSyntaxException', 'ParserElement', 'QuotedString', 'RecursiveGrammarException',
+'Regex', 'SkipTo', 'StringEnd', 'StringStart', 'Suppress', 'Token', 'TokenConverter', 'Upcase',
+'White', 'Word', 'WordEnd', 'WordStart', 'ZeroOrMore',
+'alphanums', 'alphas', 'alphas8bit', 'anyCloseTag', 'anyOpenTag', 'cStyleComment', 'col',
+'commaSeparatedList', 'commonHTMLEntity', 'countedArray', 'cppStyleComment', 'dblQuotedString',
+'dblSlashComment', 'delimitedList', 'dictOf', 'downcaseTokens', 'empty', 'getTokensEndLoc', 'hexnums',
+'htmlComment', 'javaStyleComment', 'keepOriginalText', 'line', 'lineEnd', 'lineStart', 'lineno',
+'makeHTMLTags', 'makeXMLTags', 'matchOnlyAtCol', 'matchPreviousExpr', 'matchPreviousLiteral',
+'nestedExpr', 'nullDebugAction', 'nums', 'oneOf', 'opAssoc', 'operatorPrecedence', 'printables',
+'punc8bit', 'pythonStyleComment', 'quotedString', 'removeQuotes', 'replaceHTMLEntity',
+'replaceWith', 'restOfLine', 'sglQuotedString', 'srange', 'stringEnd',
+'stringStart', 'traceParseAction', 'unicodeString', 'upcaseTokens', 'withAttribute',
+'indentedBlock',
+]
+
+
+"""
+Detect if we are running version 3.X and make appropriate changes
+Robert A. Clark
+"""
+if sys.version_info[0] > 2:
+    _PY3K = True
+    _MAX_INT = sys.maxsize
+    basestring = str
+else:
+    _PY3K = False
+    _MAX_INT = sys.maxint
+
+if not _PY3K:
+    def _ustr(obj):
+        """Drop-in replacement for str(obj) that tries to be Unicode friendly. It first tries
+           str(obj). If that fails with a UnicodeEncodeError, then it tries unicode(obj). It
+           then < returns the unicode object | encodes it with the default encoding | ... >.
+        """
+        try:
+            # If this works, then _ustr(obj) has the same behaviour as str(obj), so
+            # it won't break any existing code.
+            return str(obj)
+
+        except UnicodeEncodeError:
+            # The Python docs (http://docs.python.org/ref/customization.html#l2h-182)
+            # state that "The return value must be a string object". However, does a
+            # unicode object (being a subclass of basestring) count as a "string
+            # object"?
+            # If so, then return a unicode object:
+            return unicode(obj)
+            # Else encode it... but how? There are many choices... :)
+            # Replace unprintables with escape codes?
+            #return unicode(obj).encode(sys.getdefaultencoding(), 'backslashreplace_errors')
+            # Replace unprintables with question marks?
+            #return unicode(obj).encode(sys.getdefaultencoding(), 'replace')
+            # ...
+else:
+    _ustr = str
 
 def _str2dict(strg):
     return dict( [(c,0) for c in strg] )
-
-alphas     = string.lowercase + string.uppercase
+    #~ return set( [c for c in strg] )
+
+class _Constants(object):
+    pass
+
+if not _PY3K:
+    alphas     = string.lowercase + string.uppercase
+else:
+    alphas     = string.ascii_lowercase + string.ascii_uppercase
 nums       = string.digits
 hexnums    = nums + "ABCDEFabcdef"
-alphanums  = alphas + nums    
+alphanums  = alphas + nums
+_bslash = "\\"
+printables = "".join( [ c for c in string.printable if c not in string.whitespace ] )
 
 class ParseBaseException(Exception):
     """base exception class for all parsing runtime exceptions"""
     __slots__ = ( "loc","msg","pstr","parserElement" )
     # Performance tuning: we construct a *lot* of these, so keep this
-    # constructor as small and fast as possible        
-    def __init__( self, pstr, loc, msg, elem=None ):
+    # constructor as small and fast as possible
+    def __init__( self, pstr, loc=0, msg=None, elem=None ):
         self.loc = loc
-        self.msg = msg
-        self.pstr = pstr
+        if msg is None:
+            self.msg = pstr
+            self.pstr = ""
+        else:
+            self.msg = msg
+            self.pstr = pstr
         self.parserElement = elem
 
     def __getattr__( self, aname ):
         elif( aname == "line" ):
             return line( self.loc, self.pstr )
         else:
-            raise AttributeError, aname
+            raise AttributeError(aname)
 
     def __str__( self ):
-        return "%s (at char %d), (line:%d, col:%d)" % ( self.msg, self.loc, self.lineno, self.column )
+        return "%s (at char %d), (line:%d, col:%d)" % \
+                ( self.msg, self.loc, self.lineno, self.column )
     def __repr__( self ):
         return _ustr(self)
     def markInputline( self, markerString = ">!<" ):
-        """Extracts the exception line from the input string, and marks 
+        """Extracts the exception line from the input string, and marks
            the location of the exception with a special symbol.
         """
         line_str = self.line
         line_column = self.column - 1
         if markerString:
-            line_str = "".join( [line_str[:line_column], markerString, line_str[line_column:]])
+            line_str = "".join( [line_str[:line_column],
+                                markerString, line_str[line_column:]])
         return line_str.strip()
 
 class ParseException(ParseBaseException):
-    """exception thrown when parse expressions don't match class"""
-    """supported attributes by name are:
+    """exception thrown when parse expressions don't match class;
+       supported attributes by name are:
         - lineno - returns the line number of the exception text
         - col - returns the column number of the exception text
         - line - returns the line containing the exception text
     """
     pass
-    
+
 class ParseFatalException(ParseBaseException):
     """user-throwable exception thrown when inconsistent parse content
        is found; stops all parsing immediately"""
     pass
-    
+
+class ParseSyntaxException(ParseFatalException):
+    """just like ParseFatalException, but thrown internally when an
+       ErrorStop indicates that parsing is to stop immediately because
+       an unbacktrackable syntax error has been found"""
+    def __init__(self, pe):
+        super(ParseSyntaxException, self).__init__(
+                                    pe.pstr, pe.loc, pe.msg, pe.parserElement)
+
+#~ class ReparseException(ParseBaseException):
+    #~ """Experimental class - parse actions can raise this exception to cause
+       #~ pyparsing to reparse the input string:
+        #~ - with a modified input string, and/or
+        #~ - with a modified start location
+       #~ Set the values of the ReparseException in the constructor, and raise the
+       #~ exception in a parse action to cause pyparsing to use the new string/location.
+       #~ Setting the values as None causes no change to be made.
+       #~ """
+    #~ def __init_( self, newstring, restartLoc ):
+        #~ self.newParseText = newstring
+        #~ self.reparseLoc = restartLoc
+
 class RecursiveGrammarException(Exception):
     """exception thrown by validate() if the grammar could be improperly recursive"""
     def __init__( self, parseElementList ):
         self.parseElementTrace = parseElementList
-    
+
     def __str__( self ):
         return "RecursiveGrammarException: %s" % self.parseElementTrace
 
+class _ParseResultsWithOffset(object):
+    def __init__(self,p1,p2):
+        self.tup = (p1,p2)
+    def __getitem__(self,i):
+        return self.tup[i]
+    def __repr__(self):
+        return repr(self.tup)
+
 class ParseResults(object):
     """Structured parse results, to provide multiple means of access to the parsed data:
        - as a list (len(results))
        - by list index (results[0], results[1], etc.)
        - by attribute (results.<resultsName>)
        """
-    __slots__ = ( "__toklist", "__tokdict", "__doinit", "__name", "__parent", "__modal" )
+    __slots__ = ( "__toklist", "__tokdict", "__doinit", "__name", "__parent", "__accumNames", "__weakref__" )
     def __new__(cls, toklist, name=None, asList=True, modal=True ):
         if isinstance(toklist, cls):
             return toklist
         retobj = object.__new__(cls)
         retobj.__doinit = True
         return retobj
-        
+
     # Performance tuning: we construct a *lot* of these, so keep this
     # constructor as small and fast as possible
     def __init__( self, toklist, name=None, asList=True, modal=True ):
             self.__doinit = False
             self.__name = None
             self.__parent = None
-            self.__modal = modal
+            self.__accumNames = {}
             if isinstance(toklist, list):
                 self.__toklist = toklist[:]
             else:
 
         # this line is related to debugging the asXML bug
         #~ asList = False
-        
+
         if name:
-            if not self.__name:
-                self.__modal = self.__modal and modal
+            if not modal:
+                self.__accumNames[name] = 0
             if isinstance(name,int):
                 name = _ustr(name) # will always return a str, but use _ustr for consistency
             self.__name = name
             if not toklist in (None,'',[]):
-                if isinstance(toklist,basestring): 
+                if isinstance(toklist,basestring):
                     toklist = [ toklist ]
                 if asList:
                     if isinstance(toklist,ParseResults):
-                        self[name] = (toklist.copy(),-1)
+                        self[name] = _ParseResultsWithOffset(toklist.copy(),-1)
                     else:
-                        self[name] = (ParseResults(toklist[0]),-1)
+                        self[name] = _ParseResultsWithOffset(ParseResults(toklist[0]),-1)
                     self[name].__name = name
                 else:
                     try:
                         self[name] = toklist[0]
-                    except TypeError:
+                    except (KeyError,TypeError):
                         self[name] = toklist
 
     def __getitem__( self, i ):
         if isinstance( i, (int,slice) ):
             return self.__toklist[i]
         else:
-            if self.__modal:
+            if i not in self.__accumNames:
                 return self.__tokdict[i][-1][0]
             else:
                 return ParseResults([ v[0] for v in self.__tokdict[i] ])
 
     def __setitem__( self, k, v ):
-        if isinstance(v,tuple):
+        if isinstance(v,_ParseResultsWithOffset):
             self.__tokdict[k] = self.__tokdict.get(k,list()) + [v]
             sub = v[0]
+        elif isinstance(k,int):
+            self.__toklist[k] = v
+            sub = v
         else:
-            self.__tokdict[k] = self.__tokdict.get(k,list()) + [(v,0)]
+            self.__tokdict[k] = self.__tokdict.get(k,list()) + [_ParseResultsWithOffset(v,0)]
             sub = v
         if isinstance(sub,ParseResults):
-            sub.__parent = self
-        
+            sub.__parent = wkref(self)
+
     def __delitem__( self, i ):
-        del self.__toklist[i]
+        if isinstance(i,(int,slice)):
+            mylen = len( self.__toklist )
+            del self.__toklist[i]
+
+            # convert int to slice
+            if isinstance(i, int):
+                if i < 0:
+                    i += mylen
+                i = slice(i, i+1)
+            # get removed indices
+            removed = list(range(*i.indices(mylen)))
+            removed.reverse()
+            # fixup indices in token dictionary
+            for name in self.__tokdict:
+                occurrences = self.__tokdict[name]
+                for j in removed:
+                    for k, (value, position) in enumerate(occurrences):
+                        occurrences[k] = _ParseResultsWithOffset(value, position - (position > j))
+        else:
+            del self.__tokdict[i]
 
     def __contains__( self, k ):
-        return self.__tokdict.has_key(k)
-        
+        return k in self.__tokdict
+
     def __len__( self ): return len( self.__toklist )
+    def __bool__(self): return len( self.__toklist ) > 0
+    __nonzero__ = __bool__
     def __iter__( self ): return iter( self.__toklist )
-    def keys( self ): 
+    def __reversed__( self ): return iter( reversed(self.__toklist) )
+    def keys( self ):
         """Returns all named result keys."""
         return self.__tokdict.keys()
-    
-    def items( self ): 
+
+    def pop( self, index=-1 ):
+        """Removes and returns item at specified index (default=last).
+           Will work with either numeric indices or dict-key indicies."""
+        ret = self[index]
+        del self[index]
+        return ret
+
+    def get(self, key, defaultValue=None):
+        """Returns named result matching the given key, or if there is no
+           such name, then returns the given defaultValue or None if no
+           defaultValue is specified."""
+        if key in self:
+            return self[key]
+        else:
+            return defaultValue
+
+    def insert( self, index, insStr ):
+        self.__toklist.insert(index, insStr)
+        # fixup indices in token dictionary
+        for name in self.__tokdict:
+            occurrences = self.__tokdict[name]
+            for k, (value, position) in enumerate(occurrences):
+                occurrences[k] = _ParseResultsWithOffset(value, position + (position > j))
+
+    def items( self ):
         """Returns all named result keys and values as a list of tuples."""
-        return [(k,v[-1][0]) for k,v in self.__tokdict.items()]
-    
-    def values( self ): 
+        return [(k,self[k]) for k in self.__tokdict]
+
+    def values( self ):
         """Returns all named result values."""
         return [ v[-1][0] for v in self.__tokdict.values() ]
 
     def __getattr__( self, name ):
         if name not in self.__slots__:
-            if self.__tokdict.has_key( name ):
-                if self.__modal:
+            if name in self.__tokdict:
+                if name not in self.__accumNames:
                     return self.__tokdict[name][-1][0]
                 else:
                     return ParseResults([ v[0] for v in self.__tokdict[name] ])
                 return ""
         return None
 
+    def __add__( self, other ):
+        ret = self.copy()
+        ret += other
+        return ret
+
     def __iadd__( self, other ):
         if other.__tokdict:
             offset = len(self.__toklist)
             addoffset = ( lambda a: (a<0 and offset) or (a+offset) )
-            otherdictitems = [(k,(v[0],addoffset(v[1])) ) for (k,vlist) in other.__tokdict.items() for v in vlist]
+            otheritems = other.__tokdict.items()
+            otherdictitems = [(k, _ParseResultsWithOffset(v[0],addoffset(v[1])) )
+                                for (k,vlist) in otheritems for v in vlist]
             for k,v in otherdictitems:
                 self[k] = v
                 if isinstance(v[0],ParseResults):
-                    v[0].__parent = self
+                    v[0].__parent = wkref(self)
         self.__toklist += other.__toklist
+        self.__accumNames.update( other.__accumNames )
         del other
         return self
-       
+
     def __repr__( self ):
         return "(%s, %s)" % ( repr( self.__toklist ), repr( self.__tokdict ) )
 
         ret = ParseResults( self.__toklist )
         ret.__tokdict = self.__tokdict.copy()
         ret.__parent = self.__parent
-        ret.__modal = self.__modal
+        ret.__accumNames.update( self.__accumNames )
         ret.__name = self.__name
         return ret
-        
+
     def asXML( self, doctag=None, namedItemsOnly=False, indent="", formatted=True ):
         """Returns the parse results as XML. Tags are created for tokens and lists that have defined results names."""
         nl = "\n"
         out = []
-        namedItems = dict( [ (v[1],k) for (k,vlist) in self.__tokdict.items() for v in vlist ] )
+        namedItems = dict( [ (v[1],k) for (k,vlist) in self.__tokdict.items()
+                                                            for v in vlist ] )
         nextLevelIndent = indent + "  "
-        
+
         # collapse out indents if formatting is not desired
         if not formatted:
             indent = ""
             nextLevelIndent = ""
             nl = ""
-            
+
         selfTag = None
         if doctag is not None:
             selfTag = doctag
         else:
             if self.__name:
                 selfTag = self.__name
-        
+
         if not selfTag:
             if namedItemsOnly:
                 return ""
             else:
                 selfTag = "ITEM"
-                
+
         out += [ nl, indent, "<", selfTag, ">" ]
-        
+
         worklist = self.__toklist
         for i,res in enumerate(worklist):
             if isinstance(res,ParseResults):
                 if i in namedItems:
-                    out += [ res.asXML(namedItems[i], namedItemsOnly and doctag is None, nextLevelIndent,formatted)]
+                    out += [ res.asXML(namedItems[i],
+                                        namedItemsOnly and doctag is None,
+                                        nextLevelIndent,
+                                        formatted)]
                 else:
-                    out += [ res.asXML(None, namedItemsOnly and doctag is None, nextLevelIndent,formatted)]
+                    out += [ res.asXML(None,
+                                        namedItemsOnly and doctag is None,
+                                        nextLevelIndent,
+                                        formatted)]
             else:
                 # individual token, see if there is a name for it
                 resTag = None
                         continue
                     else:
                         resTag = "ITEM"
-                out += [ nl, nextLevelIndent, "<", resTag, ">", _ustr(res), "</", resTag, ">" ]
-        
+                xmlBodyText = xml.sax.saxutils.escape(_ustr(res))
+                out += [ nl, nextLevelIndent, "<", resTag, ">",
+                                                xmlBodyText,
+                                                "</", resTag, ">" ]
+
         out += [ nl, indent, "</", selfTag, ">" ]
         return "".join(out)
 
-
     def __lookup(self,sub):
         for k,vlist in self.__tokdict.items():
             for v,loc in vlist:
                 if sub is v:
                     return k
         return None
-            
+
     def getName(self):
         """Returns the results name for this token expression."""
         if self.__name:
             return self.__name
         elif self.__parent:
-            par = self.__parent
+            par = self.__parent()
             if par:
                 return par.__lookup(self)
             else:
                 return None
-        elif (len(self) == 1 and 
+        elif (len(self) == 1 and
                len(self.__tokdict) == 1 and
                self.__tokdict.values()[0][0][1] in (0,-1)):
             return self.__tokdict.keys()[0]
         else:
             return None
 
+    def dump(self,indent='',depth=0):
+        """Diagnostic method for listing out the contents of a ParseResults.
+           Accepts an optional indent argument so that this string can be embedded
+           in a nested display of other data."""
+        out = []
+        out.append( indent+_ustr(self.asList()) )
+        keys = self.items()
+        keys.sort()
+        for k,v in keys:
+            if out:
+                out.append('\n')
+            out.append( "%s%s- %s: " % (indent,('  '*depth), k) )
+            if isinstance(v,ParseResults):
+                if v.keys():
+                    #~ out.append('\n')
+                    out.append( v.dump(indent,depth+1) )
+                    #~ out.append('\n')
+                else:
+                    out.append(_ustr(v))
+            else:
+                out.append(_ustr(v))
+        #~ out.append('\n')
+        return "".join(out)
+
+    # add support for pickle protocol
+    def __getstate__(self):
+        return ( self.__toklist,
+                 ( self.__tokdict.copy(),
+                   self.__parent is not None and self.__parent() or None,
+                   self.__accumNames,
+                   self.__name ) )
+
+    def __setstate__(self,state):
+        self.__toklist = state[0]
+        self.__tokdict, \
+        par, \
+        inAccumNames, \
+        self.__name = state[1]
+        self.__accumNames = {}
+        self.__accumNames.update(inAccumNames)
+        if par is not None:
+            self.__parent = wkref(par)
+        else:
+            self.__parent = None
+
+
 def col (loc,strg):
     """Returns current column within a string, counting newlines as line separators.
    The first column is number 1.
+
+   Note: the default parsing behavior is to expand tabs in the input string
+   before starting the parsing process.  See L{I{ParserElement.parseString}<ParserElement.parseString>} for more information
+   on parsing strings containing <TAB>s, and suggested methods to maintain a
+   consistent view of the parsed string, the parse location, and line and column
+   positions within the parsed string.
    """
-    return loc - strg.rfind("\n", 0, loc)
+    return (loc<len(strg) and strg[loc] == '\n') and 1 or loc - strg.rfind("\n", 0, loc)
 
 def lineno(loc,strg):
     """Returns current line number within a string, counting newlines as line separators.
    The first line is number 1.
+
+   Note: the default parsing behavior is to expand tabs in the input string
+   before starting the parsing process.  See L{I{ParserElement.parseString}<ParserElement.parseString>} for more information
+   on parsing strings containing <TAB>s, and suggested methods to maintain a
+   consistent view of the parsed string, the parse location, and line and column
+   positions within the parsed string.
    """
     return strg.count("\n",0,loc) + 1
 
         return strg[lastCR+1:]
 
 def _defaultStartDebugAction( instring, loc, expr ):
-    print "Match",expr,"at loc",loc,"(%d,%d)" % ( lineno(loc,instring), col(loc,instring) )
+    print ("Match " + _ustr(expr) + " at loc " + _ustr(loc) + "(%d,%d)" % ( lineno(loc,instring), col(loc,instring) ))
 
 def _defaultSuccessDebugAction( instring, startloc, endloc, expr, toks ):
-    print "Matched",expr,"->",toks.asList()
-    
+    print ("Matched " + _ustr(expr) + " -> " + str(toks.asList()))
+
 def _defaultExceptionDebugAction( instring, loc, expr, exc ):
-    print "Exception raised:", exc
+    print ("Exception raised:" + _ustr(exc))
 
 def nullDebugAction(*args):
     """'Do-nothing' debug action, to suppress debugging output during parsing."""
         """
         ParserElement.DEFAULT_WHITE_CHARS = chars
     setDefaultWhitespaceChars = staticmethod(setDefaultWhitespaceChars)
-    
+
     def __init__( self, savelist=False ):
-        self.parseAction = None
+        self.parseAction = list()
+        self.failAction = None
         #~ self.name = "<unknown>"  # don't define self.name, let subclasses try/except upcall
         self.strRepr = None
         self.resultsName = None
         self.saveAsList = savelist
         self.skipWhitespace = True
         self.whiteChars = ParserElement.DEFAULT_WHITE_CHARS
-        self.mayReturnEmpty = False
+        self.copyDefaultWhiteChars = True
+        self.mayReturnEmpty = False # used when checking for left-recursion
         self.keepTabs = False
-        self.ignoreExprs = []
+        self.ignoreExprs = list()
         self.debug = False
         self.streamlined = False
-        self.mayIndexError = True
+        self.mayIndexError = True # used to optimize exception handling for subclasses that don't advance parse index
         self.errmsg = ""
-        self.modalResults = True
-        self.debugActions = ( None, None, None )
+        self.modalResults = True # used to mark results names as modal (report only last) or cumulative (list all)
+        self.debugActions = ( None, None, None ) #custom debug actions
         self.re = None
+        self.callPreparse = True # used to avoid redundant calls to preParse
+        self.callDuringTry = False
 
     def copy( self ):
         """Make a copy of this ParserElement.  Useful for defining different parse actions
            for the same parsing pattern, using copies of the original parse element."""
         cpy = copy.copy( self )
-        cpy.whiteChars = ParserElement.DEFAULT_WHITE_CHARS
+        cpy.parseAction = self.parseAction[:]
+        cpy.ignoreExprs = self.ignoreExprs[:]
+        if self.copyDefaultWhiteChars:
+            cpy.whiteChars = ParserElement.DEFAULT_WHITE_CHARS
         return cpy
 
     def setName( self, name ):
         """Define name for this expression, for use in debugging."""
         self.name = name
         self.errmsg = "Expected " + self.name
+        if hasattr(self,"exception"):
+            self.exception.msg = self.errmsg
         return self
 
     def setResultsName( self, name, listAllMatches=False ):
-        """Define name for referencing matching tokens as a nested attribute 
+        """Define name for referencing matching tokens as a nested attribute
            of the returned parse results.
            NOTE: this returns a *copy* of the original ParserElement object;
            this is so that the client can define a basic element, such as an
         newself.modalResults = not listAllMatches
         return newself
 
-    def setParseAction( self, fn ):
+    def setBreak(self,breakFlag = True):
+        """Method to invoke the Python pdb debugger when this element is
+           about to be parsed. Set breakFlag to True to enable, False to
+           disable.
+        """
+        if breakFlag:
+            _parseMethod = self._parse
+            def breaker(instring, loc, doActions=True, callPreParse=True):
+                import pdb
+                pdb.set_trace()
+                _parseMethod( instring, loc, doActions, callPreParse )
+            breaker._originalParseMethod = _parseMethod
+            self._parse = breaker
+        else:
+            if hasattr(self._parse,"_originalParseMethod"):
+                self._parse = self._parse._originalParseMethod
+        return self
+
+    def _normalizeParseActionArgs( f ):
+        """Internal method used to decorate parse actions that take fewer than 3 arguments,
+           so that all parse actions can be called as f(s,l,t)."""
+        STAR_ARGS = 4
+
+        try:
+            restore = None
+            if isinstance(f,type):
+                restore = f
+                f = f.__init__
+            if not _PY3K:
+                codeObj = f.func_code
+            else:
+                codeObj = f.code
+            if codeObj.co_flags & STAR_ARGS:
+                return f
+            numargs = codeObj.co_argcount
+            if not _PY3K:
+                if hasattr(f,"im_self"):
+                    numargs -= 1
+            else:
+                if hasattr(f,"__self__"):
+                    numargs -= 1
+            if restore:
+                f = restore
+        except AttributeError:
+            try:
+                if not _PY3K:
+                    call_im_func_code = f.__call__.im_func.func_code
+                else:
+                    call_im_func_code = f.__code__
+
+                # not a function, must be a callable object, get info from the
+                # im_func binding of its bound __call__ method
+                if call_im_func_code.co_flags & STAR_ARGS:
+                    return f
+                numargs = call_im_func_code.co_argcount
+                if not _PY3K:
+                    if hasattr(f.__call__,"im_self"):
+                        numargs -= 1
+                else:
+                    if hasattr(f.__call__,"__self__"):
+                        numargs -= 0
+            except AttributeError:
+                if not _PY3K:
+                    call_func_code = f.__call__.func_code
+                else:
+                    call_func_code = f.__call__.__code__
+                # not a bound method, get info directly from __call__ method
+                if call_func_code.co_flags & STAR_ARGS:
+                    return f
+                numargs = call_func_code.co_argcount
+                if not _PY3K:
+                    if hasattr(f.__call__,"im_self"):
+                        numargs -= 1
+                else:
+                    if hasattr(f.__call__,"__self__"):
+                        numargs -= 1
+
+
+        #~ print ("adding function %s with %d args" % (f.func_name,numargs))
+        if numargs == 3:
+            return f
+        else:
+            if numargs > 3:
+                def tmp(s,l,t):
+                    return f(f.__call__.__self__, s,l,t)
+            if numargs == 2:
+                def tmp(s,l,t):
+                    return f(l,t)
+            elif numargs == 1:
+                def tmp(s,l,t):
+                    return f(t)
+            else: #~ numargs == 0:
+                def tmp(s,l,t):
+                    return f()
+            try:
+                tmp.__name__ = f.__name__
+            except (AttributeError,TypeError):
+                # no need for special handling if attribute doesnt exist
+                pass
+            try:
+                tmp.__doc__ = f.__doc__
+            except (AttributeError,TypeError):
+                # no need for special handling if attribute doesnt exist
+                pass
+            try:
+                tmp.__dict__.update(f.__dict__)
+            except (AttributeError,TypeError):
+                # no need for special handling if attribute doesnt exist
+                pass
+            return tmp
+    _normalizeParseActionArgs = staticmethod(_normalizeParseActionArgs)
+
+    def setParseAction( self, *fns, **kwargs ):
         """Define action to perform when successfully matching parse element definition.
-           Parse action fn is a callable method with the arguments (s, loc, toks) where:
-            - s   = the original string being parsed
+           Parse action fn is a callable method with 0-3 arguments, called as fn(s,loc,toks),
+           fn(loc,toks), fn(toks), or just fn(), where:
+            - s   = the original string being parsed (see note below)
             - loc = the location of the matching substring
             - toks = a list of the matched tokens, packaged as a ParseResults object
-           If the function fn modifies the tokens, it can return them as the return
+           If the functions in fns modify the tokens, they can return them as the return
            value from fn, and the modified list of tokens will replace the original.
            Otherwise, fn does not need to return any value.
-        """
-        self.parseAction = fn
+
+           Note: the default parsing behavior is to expand tabs in the input string
+           before starting the parsing process.  See L{I{parseString}<parseString>} for more information
+           on parsing strings containing <TAB>s, and suggested methods to maintain a
+           consistent view of the parsed string, the parse location, and line and column
+           positions within the parsed string.
+           """
+        self.parseAction = list(map(self._normalizeParseActionArgs, list(fns)))
+        self.callDuringTry = ("callDuringTry" in kwargs and kwargs["callDuringTry"])
         return self
 
-    def skipIgnorables( self, instring, loc ):
+    def addParseAction( self, *fns, **kwargs ):
+        """Add parse action to expression's list of parse actions. See L{I{setParseAction}<setParseAction>}."""
+        self.parseAction += list(map(self._normalizeParseActionArgs, list(fns)))
+        self.callDuringTry = self.callDuringTry or ("callDuringTry" in kwargs and kwargs["callDuringTry"])
+        return self
+
+    def setFailAction( self, fn ):
+        """Define action to perform if parsing fails at this expression.
+           Fail acton fn is a callable function that takes the arguments
+           fn(s,loc,expr,err) where:
+            - s = string being parsed
+            - loc = location where expression match was attempted and failed
+            - expr = the parse expression that failed
+            - err = the exception thrown
+           The function returns no value.  It may throw ParseFatalException
+           if it is desired to stop parsing immediately."""
+        self.failAction = fn
+        return self
+
+    def _skipIgnorables( self, instring, loc ):
         exprsFound = True
         while exprsFound:
             exprsFound = False
             for e in self.ignoreExprs:
                 try:
                     while 1:
-                        loc,dummy = e.parse( instring, loc )
+                        loc,dummy = e._parse( instring, loc )
                         exprsFound = True
                 except ParseException:
                     pass
 
     def preParse( self, instring, loc ):
         if self.ignoreExprs:
-            loc = self.skipIgnorables( instring, loc )
-        
+            loc = self._skipIgnorables( instring, loc )
+
         if self.skipWhitespace:
             wt = self.whiteChars
             instrlen = len(instring)
             while loc < instrlen and instring[loc] in wt:
                 loc += 1
-                
+
         return loc
 
     def parseImpl( self, instring, loc, doActions=True ):
         return tokenlist
 
     #~ @profile
-    def parse( self, instring, loc, doActions=True, callPreParse=True ):
+    def _parseNoCache( self, instring, loc, doActions=True, callPreParse=True ):
         debugging = ( self.debug ) #and doActions )
 
-        if debugging:
-            #~ print "Match",self,"at loc",loc,"(%d,%d)" % ( lineno(loc,instring), col(loc,instring) )
+        if debugging or self.failAction:
+            #~ print ("Match",self,"at loc",loc,"(%d,%d)" % ( lineno(loc,instring), col(loc,instring) ))
             if (self.debugActions[0] ):
                 self.debugActions[0]( instring, loc, self )
-            if callPreParse:
-                loc = self.preParse( instring, loc )
+            if callPreParse and self.callPreparse:
+                preloc = self.preParse( instring, loc )
+            else:
+                preloc = loc
             tokensStart = loc
             try:
                 try:
-                    loc,tokens = self.parseImpl( instring, loc, doActions )
+                    loc,tokens = self.parseImpl( instring, preloc, doActions )
                 except IndexError:
-                    raise ParseException, ( instring, len(instring), self.errmsg, self )
-            except ParseException, err:
-                #~ print "Exception raised:", err
-                if (self.debugActions[2] ):
+                    raise ParseException( instring, len(instring), self.errmsg, self )
+            except ParseBaseException, err:
+                #~ print ("Exception raised:", err)
+                if self.debugActions[2]:
                     self.debugActions[2]( instring, tokensStart, self, err )
+                if self.failAction:
+                    self.failAction( instring, tokensStart, self, err )
                 raise
         else:
-            if callPreParse:
-                loc = self.preParse( instring, loc )
+            if callPreParse and self.callPreparse:
+                preloc = self.preParse( instring, loc )
+            else:
+                preloc = loc
             tokensStart = loc
             if self.mayIndexError or loc >= len(instring):
                 try:
-                    loc,tokens = self.parseImpl( instring, loc, doActions )
+                    loc,tokens = self.parseImpl( instring, preloc, doActions )
                 except IndexError:
-                    raise ParseException, ( instring, len(instring), self.errmsg, self )
+                    raise ParseException( instring, len(instring), self.errmsg, self )
             else:
-                loc,tokens = self.parseImpl( instring, loc, doActions )
-        
+                loc,tokens = self.parseImpl( instring, preloc, doActions )
+
         tokens = self.postParse( instring, loc, tokens )
 
         retTokens = ParseResults( tokens, self.resultsName, asList=self.saveAsList, modal=self.modalResults )
-        if self.parseAction and doActions:
+        if self.parseAction and (doActions or self.callDuringTry):
             if debugging:
                 try:
-                    tokens = self.parseAction( instring, tokensStart, retTokens )
-                    if tokens is not None:
-                        if isinstance(tokens,tuple):
-                            tokens = tokens[1]
-                        retTokens = ParseResults( tokens, 
-                                                  self.resultsName, 
-                                                  asList=self.saveAsList and isinstance(tokens,(ParseResults,list)), 
-                                                  modal=self.modalResults )
-                except ParseException, err:
+                    for fn in self.parseAction:
+                        tokens = fn( instring, tokensStart, retTokens )
+                        if tokens is not None:
+                            retTokens = ParseResults( tokens,
+                                                      self.resultsName,
+                                                      asList=self.saveAsList and isinstance(tokens,(ParseResults,list)),
+                                                      modal=self.modalResults )
+                except ParseBaseException, err:
                     #~ print "Exception raised in user parse action:", err
                     if (self.debugActions[2] ):
                         self.debugActions[2]( instring, tokensStart, self, err )
                     raise
             else:
-                tokens = self.parseAction( instring, tokensStart, retTokens )
-                if tokens is not None:
-                    if isinstance(tokens,tuple):
-                        tokens = tokens[1]
-                    retTokens = ParseResults( tokens, 
-                                              self.resultsName, 
-                                              asList=self.saveAsList and isinstance(tokens,(ParseResults,list)), 
-                                              modal=self.modalResults )
+                for fn in self.parseAction:
+                    tokens = fn( instring, tokensStart, retTokens )
+                    if tokens is not None:
+                        retTokens = ParseResults( tokens,
+                                                  self.resultsName,
+                                                  asList=self.saveAsList and isinstance(tokens,(ParseResults,list)),
+                                                  modal=self.modalResults )
 
         if debugging:
-            #~ print "Matched",self,"->",retTokens.asList()
+            #~ print ("Matched",self,"->",retTokens.asList())
             if (self.debugActions[1] ):
                 self.debugActions[1]( instring, tokensStart, loc, self, retTokens )
 
         return loc, retTokens
 
     def tryParse( self, instring, loc ):
-        return self.parse( instring, loc, doActions=False )[0]
-
-    def parseString( self, instring ):
+        try:
+            return self._parse( instring, loc, doActions=False )[0]
+        except ParseFatalException:
+            raise ParseException( instring, loc, self.errmsg, self)
+
+    # this method gets repeatedly called during backtracking with the same arguments -
+    # we can cache these arguments and save ourselves the trouble of re-parsing the contained expression
+    def _parseCache( self, instring, loc, doActions=True, callPreParse=True ):
+        lookup = (self,instring,loc,callPreParse,doActions)
+        if lookup in ParserElement._exprArgCache:
+            value = ParserElement._exprArgCache[ lookup ]
+            if isinstance(value,Exception):
+                raise value
+            return value
+        else:
+            try:
+                value = self._parseNoCache( instring, loc, doActions, callPreParse )
+                ParserElement._exprArgCache[ lookup ] = (value[0],value[1].copy())
+                return value
+            except ParseBaseException, pe:
+                ParserElement._exprArgCache[ lookup ] = pe
+                raise
+
+    _parse = _parseNoCache
+
+    # argument cache for optimizing repeated calls when backtracking through recursive expressions
+    _exprArgCache = {}
+    def resetCache():
+        ParserElement._exprArgCache.clear()
+    resetCache = staticmethod(resetCache)
+
+    _packratEnabled = False
+    def enablePackrat():
+        """Enables "packrat" parsing, which adds memoizing to the parsing logic.
+           Repeated parse attempts at the same string location (which happens
+           often in many complex grammars) can immediately return a cached value,
+           instead of re-executing parsing/validating code.  Memoizing is done of
+           both valid results and parsing exceptions.
+
+           This speedup may break existing programs that use parse actions that
+           have side-effects.  For this reason, packrat parsing is disabled when
+           you first import pyparsing.  To activate the packrat feature, your
+           program must call the class method ParserElement.enablePackrat().  If
+           your program uses psyco to "compile as you go", you must call
+           enablePackrat before calling psyco.full().  If you do not do this,
+           Python will crash.  For best results, call enablePackrat() immediately
+           after importing pyparsing.
+        """
+        if not ParserElement._packratEnabled:
+            ParserElement._packratEnabled = True
+            ParserElement._parse = ParserElement._parseCache
+    enablePackrat = staticmethod(enablePackrat)
+
+    def parseString( self, instring, parseAll=False ):
         """Execute the parse expression with the given string.
-           This is the main interface to the client code, once the complete 
+           This is the main interface to the client code, once the complete
            expression has been built.
+
+           If you want the grammar to require that the entire input string be
+           successfully parsed, then set parseAll to True (equivalent to ending
+           the grammar with StringEnd()).
+
+           Note: parseString implicitly calls expandtabs() on the input string,
+           in order to report proper column numbers in parse actions.
+           If the input string contains tabs and
+           the grammar uses parse actions that use the loc argument to index into the
+           string being parsed, you can ensure you have a consistent view of the input
+           string by:
+            - calling parseWithTabs on your grammar before calling parseString
+              (see L{I{parseWithTabs}<parseWithTabs>})
+            - define your parse action using the full (s,loc,toks) signature, and
+              reference the input string using the parse action's s argument
+            - explictly expand the tabs in your input string before calling
+              parseString
         """
+        ParserElement.resetCache()
         if not self.streamlined:
             self.streamline()
-            self.saveAsList = True
+            #~ self.saveAsList = True
         for e in self.ignoreExprs:
             e.streamline()
-        if self.keepTabs:
-            loc, tokens = self.parse( instring, 0 )
-        else:
-            loc, tokens = self.parse( instring.expandtabs(), 0 )
+        if not self.keepTabs:
+            instring = instring.expandtabs()
+        loc, tokens = self._parse( instring, 0 )
+        if parseAll:
+            StringEnd()._parse( instring, loc )
         return tokens
 
-    def scanString( self, instring ):
-        """Scan the input string for expression matches.  Each match will return the matching tokens, start location, and end location."""
+    def scanString( self, instring, maxMatches=_MAX_INT ):
+        """Scan the input string for expression matches.  Each match will return the
+           matching tokens, start location, and end location.  May be called with optional
+           maxMatches argument, to clip scanning after 'n' matches are found.
+
+           Note that the start and end locations are reported relative to the string
+           being parsed.  See L{I{parseString}<parseString>} for more information on parsing
+           strings with embedded tabs."""
         if not self.streamlined:
             self.streamline()
         for e in self.ignoreExprs:
             e.streamline()
-        
+
         if not self.keepTabs:
-            instring = instring.expandtabs()
+            instring = _ustr(instring).expandtabs()
         instrlen = len(instring)
         loc = 0
         preparseFn = self.preParse
-        parseFn = self.parse
-        while loc < instrlen:
+        parseFn = self._parse
+        ParserElement.resetCache()
+        matches = 0
+        while loc <= instrlen and matches < maxMatches:
             try:
-                loc = preparseFn( instring, loc )
-                nextLoc,tokens = parseFn( instring, loc, callPreParse=False )
+                preloc = preparseFn( instring, loc )
+                nextLoc,tokens = parseFn( instring, preloc, callPreParse=False )
             except ParseException:
-                loc += 1
+                loc = preloc+1
             else:
-                yield tokens, loc, nextLoc
+                matches += 1
+                yield tokens, preloc, nextLoc
                 loc = nextLoc
-        
+
     def transformString( self, instring ):
         """Extension to scanString, to modify matching text with modified tokens that may
-           be returned from a parse action.  To use transformString, define a grammar and 
-           attach a parse action to it that modifies the returned token list.  
-           Invoking transformString() on a target string will then scan for matches, 
-           and replace the matched text patterns according to the logic in the parse 
+           be returned from a parse action.  To use transformString, define a grammar and
+           attach a parse action to it that modifies the returned token list.
+           Invoking transformString() on a target string will then scan for matches,
+           and replace the matched text patterns according to the logic in the parse
            action.  transformString() returns the resulting transformed string."""
         out = []
         lastE = 0
                     out.append(t)
             lastE = e
         out.append(instring[lastE:])
-        return "".join(out)
-
-    def searchString( self, instring ):
+        return "".join(map(_ustr,out))
+
+    def searchString( self, instring, maxMatches=_MAX_INT ):
         """Another extension to scanString, simplifying the access to the tokens found
-           to match the given parse expression.
+           to match the given parse expression.  May be called with optional
+           maxMatches argument, to clip searching after 'n' matches are found.
         """
-        return [ t[0] for t,s,e in self.scanString( instring ) ]
-            
+        return ParseResults([ t for t,s,e in self.scanString( instring, maxMatches ) ])
+
     def __add__(self, other ):
         """Implementation of + operator - returns And"""
         if isinstance( other, basestring ):
             other = Literal( other )
         if not isinstance( other, ParserElement ):
-            warnings.warn("Cannot add element of type %s to ParserElement" % type(other),
+            warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
                     SyntaxWarning, stacklevel=2)
+            return None
         return And( [ self, other ] )
 
     def __radd__(self, other ):
-        """Implementation of += operator"""
+        """Implementation of + operator when left operand is not a ParserElement"""
         if isinstance( other, basestring ):
             other = Literal( other )
         if not isinstance( other, ParserElement ):
-            warnings.warn("Cannot add element of type %s to ParserElement" % type(other),
+            warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
                     SyntaxWarning, stacklevel=2)
+            return None
         return other + self
 
+    def __sub__(self, other):
+        """Implementation of - operator, returns And with error stop"""
+        if isinstance( other, basestring ):
+            other = Literal( other )
+        if not isinstance( other, ParserElement ):
+            warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
+                    SyntaxWarning, stacklevel=2)
+            return None
+        return And( [ self, And._ErrorStop(), other ] )
+
+    def __rsub__(self, other ):
+        """Implementation of - operator when left operand is not a ParserElement"""
+        if isinstance( other, basestring ):
+            other = Literal( other )
+        if not isinstance( other, ParserElement ):
+            warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
+                    SyntaxWarning, stacklevel=2)
+            return None
+        return other - self
+
+    def __mul__(self,other):
+        if isinstance(other,int):
+            minElements, optElements = other,0
+        elif isinstance(other,tuple):
+            if len(other)==0:
+                other = (None,None)
+            elif len(other)==1:
+                other = (other[0],None)
+            if len(other)==2:
+                if other[0] is None:
+                    other = (0, other[1])
+                if isinstance(other[0],int) and other[1] is None:
+                    if other[0] == 0:
+                        return ZeroOrMore(self)
+                    if other[0] == 1:
+                        return OneOrMore(self)
+                    else:
+                        return self*other[0] + ZeroOrMore(self)
+                elif isinstance(other[0],int) and isinstance(other[1],int):
+                    minElements, optElements = other
+                    optElements -= minElements
+                else:
+                    raise TypeError("cannot multiply 'ParserElement' and ('%s','%s') objects", type(other[0]),type(other[1]))
+            else:
+                raise TypeError("can only multiply 'ParserElement' and int or (int,int) objects")
+        else:
+            raise TypeError("cannot multiply 'ParserElement' and '%s' objects", type(other))
+
+        if minElements < 0:
+            raise ValueError("cannot multiply ParserElement by negative value")
+        if optElements < 0:
+            raise ValueError("second tuple value must be greater or equal to first tuple value")
+        if minElements == optElements == 0:
+            raise ValueError("cannot multiply ParserElement by 0 or (0,0)")
+
+        if (optElements):
+            def makeOptionalList(n):
+                if n>1:
+                    return Optional(self + makeOptionalList(n-1))
+                else:
+                    return Optional(self)
+            if minElements:
+                if minElements == 1:
+                    ret = self + makeOptionalList(optElements)
+                else:
+                    ret = And([self]*minElements) + makeOptionalList(optElements)
+            else:
+                ret = makeOptionalList(optElements)
+        else:
+            if minElements == 1:
+                ret = self
+            else:
+                ret = And([self]*minElements)
+        return ret
+
+    def __rmul__(self, other):
+        return self.__mul__(other)
+
     def __or__(self, other ):
         """Implementation of | operator - returns MatchFirst"""
         if isinstance( other, basestring ):
             other = Literal( other )
         if not isinstance( other, ParserElement ):
-            warnings.warn("Cannot add element of type %s to ParserElement" % type(other),
+            warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
                     SyntaxWarning, stacklevel=2)
+            return None
         return MatchFirst( [ self, other ] )
 
     def __ror__(self, other ):
-        """Implementation of |= operator"""
+        """Implementation of | operator when left operand is not a ParserElement"""
         if isinstance( other, basestring ):
             other = Literal( other )
         if not isinstance( other, ParserElement ):
-            warnings.warn("Cannot add element of type %s to ParserElement" % type(other),
+            warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
                     SyntaxWarning, stacklevel=2)
+            return None
         return other | self
 
     def __xor__(self, other ):
         if isinstance( other, basestring ):
             other = Literal( other )
         if not isinstance( other, ParserElement ):
-            warnings.warn("Cannot add element of type %s to ParserElement" % type(other),
+            warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
                     SyntaxWarning, stacklevel=2)
+            return None
         return Or( [ self, other ] )
 
     def __rxor__(self, other ):
-        """Implementation of ^= operator"""
+        """Implementation of ^ operator when left operand is not a ParserElement"""
         if isinstance( other, basestring ):
             other = Literal( other )
         if not isinstance( other, ParserElement ):
-            warnings.warn("Cannot add element of type %s to ParserElement" % type(other),
+            warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
                     SyntaxWarning, stacklevel=2)
+            return None
         return other ^ self
 
     def __and__(self, other ):
         if isinstance( other, basestring ):
             other = Literal( other )
         if not isinstance( other, ParserElement ):
-            warnings.warn("Cannot add element of type %s to ParserElement" % type(other),
+            warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
                     SyntaxWarning, stacklevel=2)
+            return None
         return Each( [ self, other ] )
 
     def __rand__(self, other ):
-        """Implementation of right-& operator"""
+        """Implementation of & operator when left operand is not a ParserElement"""
         if isinstance( other, basestring ):
             other = Literal( other )
         if not isinstance( other, ParserElement ):
-            warnings.warn("Cannot add element of type %s to ParserElement" % type(other),
+            warnings.warn("Cannot combine element of type %s with ParserElement" % type(other),
                     SyntaxWarning, stacklevel=2)
+            return None
         return other & self
 
     def __invert__( self ):
         """Implementation of ~ operator - returns NotAny"""
         return NotAny( self )
 
+    def __call__(self, name):
+        """Shortcut for setResultsName, with listAllMatches=default::
+             userdata = Word(alphas).setResultsName("name") + Word(nums+"-").setResultsName("socsecno")
+           could be written as::
+             userdata = Word(alphas)("name") + Word(nums+"-")("socsecno")
+           """
+        return self.setResultsName(name)
+
     def suppress( self ):
         """Suppresses the output of this ParserElement; useful to keep punctuation from
            cluttering up returned output.
         return Suppress( self )
 
     def leaveWhitespace( self ):
-        """Disables the skipping of whitespace before matching the characters in the 
+        """Disables the skipping of whitespace before matching the characters in the
            ParserElement's defined pattern.  This is normally only used internally by
            the pyparsing module, but may be needed in some whitespace-sensitive grammars.
         """
         """
         self.skipWhitespace = True
         self.whiteChars = chars
-        
+        self.copyDefaultWhiteChars = False
+        return self
+
     def parseWithTabs( self ):
         """Overrides default behavior to expand <TAB>s to spaces before parsing the input string.
-           Must be called before parseString when the input grammar contains elements that 
+           Must be called before parseString when the input grammar contains elements that
            match <TAB> characters."""
         self.keepTabs = True
         return self
-        
+
     def ignore( self, other ):
-        """Define expression to be ignored (e.g., comments) while doing pattern 
+        """Define expression to be ignored (e.g., comments) while doing pattern
            matching; may be called repeatedly, to define multiple comment or other
            ignorable patterns.
         """
 
     def setDebugActions( self, startAction, successAction, exceptionAction ):
         """Enable display of debugging messages while doing pattern matching."""
-        self.debugActions = (startAction or _defaultStartDebugAction, 
-                             successAction or _defaultSuccessDebugAction, 
+        self.debugActions = (startAction or _defaultStartDebugAction,
+                             successAction or _defaultSuccessDebugAction,
                              exceptionAction or _defaultExceptionDebugAction)
         self.debug = True
         return self
 
     def setDebug( self, flag=True ):
-        """Enable display of debugging messages while doing pattern matching."""
+        """Enable display of debugging messages while doing pattern matching.
+           Set flag to True to enable, False to disable."""
         if flag:
             self.setDebugActions( _defaultStartDebugAction, _defaultSuccessDebugAction, _defaultExceptionDebugAction )
         else:
 
     def __repr__( self ):
         return _ustr(self)
-        
+
     def streamline( self ):
         self.streamlined = True
         self.strRepr = None
         return self
-        
+
     def checkRecursion( self, parseElementList ):
         pass
-        
+
     def validate( self, validateTrace=[] ):
         """Check defined expressions for valid structure, check for infinite recursive definitions."""
         self.checkRecursion( [] )
             f.close()
         return self.parseString(file_contents)
 
+    def getException(self):
+        return ParseException("",0,self.errmsg,self)
+
+    def __getattr__(self,aname):
+        if aname == "myException":
+            self.myException = ret = self.getException();
+            return ret;
+        else:
+            raise AttributeError("no such attribute " + aname)
+
+    def __eq__(self,other):
+        if isinstance(other, basestring):
+            try:
+                (self + StringEnd()).parseString(_ustr(other))
+                return True
+            except ParseBaseException:
+                return False
+        else:
+            return super(ParserElement,self)==other
+
+    def __hash__(self):
+        return hash(id(self))
+
+    def __req__(self,other):
+        return self == other
+
 
 class Token(ParserElement):
     """Abstract ParserElement subclass, for defining atomic matching patterns."""
     def __init__( self ):
         super(Token,self).__init__( savelist=False )
-        self.myException = ParseException("",0,"",self)
+        #self.myException = ParseException("",0,"",self)
 
     def setName(self, name):
         s = super(Token,self).setName(name)
         self.errmsg = "Expected " + self.name
-        s.myException.msg = self.errmsg
+        #s.myException.msg = self.errmsg
         return s
 
 
         self.mayReturnEmpty = True
         self.mayIndexError = False
         self.errmsg = "Unmatchable token"
-        self.myException.msg = self.errmsg
-        
+        #self.myException.msg = self.errmsg
+
     def parseImpl( self, instring, loc, doActions=True ):
         exc = self.myException
         exc.loc = loc
         try:
             self.firstMatchChar = matchString[0]
         except IndexError:
-            warnings.warn("null string passed to Literal; use Empty() instead", 
+            warnings.warn("null string passed to Literal; use Empty() instead",
                             SyntaxWarning, stacklevel=2)
             self.__class__ = Empty
-        self.name = '"%s"' % self.match
+        self.name = '"%s"' % _ustr(self.match)
         self.errmsg = "Expected " + self.name
         self.mayReturnEmpty = False
-        self.myException.msg = self.errmsg
+        #self.myException.msg = self.errmsg
         self.mayIndexError = False
 
     # Performance tuning: this routine gets called a *lot*
         if (instring[loc] == self.firstMatchChar and
             (self.matchLen==1 or instring.startswith(self.match,loc)) ):
             return loc+self.matchLen, self.match
-        #~ raise ParseException, ( instring, loc, self.errmsg )
+        #~ raise ParseException( instring, loc, self.errmsg )
         exc = self.myException
         exc.loc = loc
         exc.pstr = instring
         raise exc
+_L = Literal
 
 class Keyword(Token):
-    """Token to exactly match a specified string as a keyword, that is, it must be 
+    """Token to exactly match a specified string as a keyword, that is, it must be
        immediately followed by a non-keyword character.  Compare with Literal::
          Literal("if") will match the leading 'if' in 'ifAndOnlyIf'.
          Keyword("if") will not; it will only match the leading 'if in 'if x=1', or 'if(y==2)'
        matching, default is False.
     """
     DEFAULT_KEYWORD_CHARS = alphanums+"_$"
-    
+
     def __init__( self, matchString, identChars=DEFAULT_KEYWORD_CHARS, caseless=False ):
         super(Keyword,self).__init__()
         self.match = matchString
         try:
             self.firstMatchChar = matchString[0]
         except IndexError:
-            warnings.warn("null string passed to Keyword; use Empty() instead", 
+            warnings.warn("null string passed to Keyword; use Empty() instead",
                             SyntaxWarning, stacklevel=2)
         self.name = '"%s"' % self.match
         self.errmsg = "Expected " + self.name
         self.mayReturnEmpty = False
-        self.myException.msg = self.errmsg
+        #self.myException.msg = self.errmsg
         self.mayIndexError = False
         self.caseless = caseless
         if caseless:
                 (loc >= len(instring)-self.matchLen or instring[loc+self.matchLen] not in self.identChars) and
                 (loc == 0 or instring[loc-1] not in self.identChars) ):
                 return loc+self.matchLen, self.match
-        #~ raise ParseException, ( instring, loc, self.errmsg )
+        #~ raise ParseException( instring, loc, self.errmsg )
         exc = self.myException
         exc.loc = loc
         exc.pstr = instring
         raise exc
-        
+
     def copy(self):
         c = super(Keyword,self).copy()
         c.identChars = Keyword.DEFAULT_KEYWORD_CHARS
         return c
-        
+
     def setDefaultKeywordChars( chars ):
         """Overrides the default Keyword chars
         """
         Keyword.DEFAULT_KEYWORD_CHARS = chars
-    setDefaultKeywordChars = staticmethod(setDefaultKeywordChars)        
+    setDefaultKeywordChars = staticmethod(setDefaultKeywordChars)
 
 
 class CaselessLiteral(Literal):
         self.returnString = matchString
         self.name = "'%s'" % self.returnString
         self.errmsg = "Expected " + self.name
-        self.myException.msg = self.errmsg
+        #self.myException.msg = self.errmsg
 
     def parseImpl( self, instring, loc, doActions=True ):
         if instring[ loc:loc+self.matchLen ].upper() == self.match:
             return loc+self.matchLen, self.returnString
-        #~ raise ParseException, ( instring, loc, self.errmsg )
+        #~ raise ParseException( instring, loc, self.errmsg )
         exc = self.myException
         exc.loc = loc
         exc.pstr = instring
         if ( (instring[ loc:loc+self.matchLen ].upper() == self.caselessmatch) and
              (loc >= len(instring)-self.matchLen or instring[loc+self.matchLen].upper() not in self.identChars) ):
             return loc+self.matchLen, self.match
-        #~ raise ParseException, ( instring, loc, self.errmsg )
+        #~ raise ParseException( instring, loc, self.errmsg )
         exc = self.myException
         exc.loc = loc
         exc.pstr = instring
        Defined with string containing all allowed initial characters,
        an optional string containing allowed body characters (if omitted,
        defaults to the initial character set), and an optional minimum,
-       maximum, and/or exact length.
+       maximum, and/or exact length.  The default value for min is 1 (a
+       minimum value < 1 is not valid); the default values for max and exact
+       are 0, meaning no maximum or exact length restriction.
     """
-    def __init__( self, initChars, bodyChars=None, min=1, max=0, exact=0 ):
+    def __init__( self, initChars, bodyChars=None, min=1, max=0, exact=0, asKeyword=False ):
         super(Word,self).__init__()
         self.initCharsOrig = initChars
         self.initChars = _str2dict(initChars)
         else:
             self.bodyCharsOrig = initChars
             self.bodyChars = _str2dict(initChars)
-            
+
         self.maxSpecified = max > 0
 
+        if min < 1:
+            raise ValueError("cannot specify a minimum length < 1; use Optional(Word()) if zero-length word is permitted")
+
         self.minLen = min
 
         if max > 0:
             self.maxLen = max
         else:
-            self.maxLen = sys.maxint
+            self.maxLen = _MAX_INT
 
         if exact > 0:
             self.maxLen = exact
 
         self.name = _ustr(self)
         self.errmsg = "Expected " + self.name
-        self.myException.msg = self.errmsg
+        #self.myException.msg = self.errmsg
         self.mayIndexError = False
-        
+        self.asKeyword = asKeyword
+
         if ' ' not in self.initCharsOrig+self.bodyCharsOrig and (min==1 and max==0 and exact==0):
             if self.bodyCharsOrig == self.initCharsOrig:
                 self.reString = "[%s]+" % _escapeRegexRangeChars(self.initCharsOrig)
                 self.reString = "[%s][%s]*" % \
                                       (_escapeRegexRangeChars(self.initCharsOrig),
                                       _escapeRegexRangeChars(self.bodyCharsOrig),)
+            if self.asKeyword:
+                self.reString = r"\b"+self.reString+r"\b"
             try:
                 self.re = re.compile( self.reString )
             except:
                 self.re = None
-        
+
     def parseImpl( self, instring, loc, doActions=True ):
         if self.re:
             result = self.re.match(instring,loc)
                 exc.loc = loc
                 exc.pstr = instring
                 raise exc
-            
+
             loc = result.end()
             return loc,result.group()
-        
+
         if not(instring[ loc ] in self.initChars):
-            #~ raise ParseException, ( instring, loc, self.errmsg )
+            #~ raise ParseException( instring, loc, self.errmsg )
             exc = self.myException
             exc.loc = loc
             exc.pstr = instring
         maxloc = min( maxloc, instrlen )
         while loc < maxloc and instring[loc] in bodychars:
             loc += 1
-            
+
         throwException = False
         if loc - start < self.minLen:
             throwException = True
         if self.maxSpecified and loc < instrlen and instring[loc] in bodychars:
             throwException = True
+        if self.asKeyword:
+            if (start>0 and instring[start-1] in bodychars) or (loc<instrlen and instring[loc] in bodychars):
+                throwException = True
 
         if throwException:
-            #~ raise ParseException, ( instring, loc, self.errmsg )
+            #~ raise ParseException( instring, loc, self.errmsg )
             exc = self.myException
             exc.loc = loc
             exc.pstr = instring
         except:
             pass
 
-            
+
         if self.strRepr is None:
-            
+
             def charsAsStr(s):
                 if len(s)>4:
                     return s[:4]+"..."
                 else:
                     return s
-            
+
             if ( self.initCharsOrig != self.bodyCharsOrig ):
                 self.strRepr = "W:(%s,%s)" % ( charsAsStr(self.initCharsOrig), charsAsStr(self.bodyCharsOrig) )
             else:
     def __init__( self, pattern, flags=0):
         """The parameters pattern and flags are passed to the re.compile() function as-is. See the Python re module for an explanation of the acceptable patterns and flags."""
         super(Regex,self).__init__()
-        
+
         if len(pattern) == 0:
-            warnings.warn("null string passed to Regex; use Empty() instead", 
+            warnings.warn("null string passed to Regex; use Empty() instead",
                     SyntaxWarning, stacklevel=2)
-    
+
         self.pattern = pattern
         self.flags = flags
-        
+
         try:
             self.re = re.compile(self.pattern, self.flags)
             self.reString = self.pattern
-        except Exception,e:
-            warnings.warn("invalid pattern (%s) passed to Regex" % pattern, 
+        except sre_constants.error:
+            warnings.warn("invalid pattern (%s) passed to Regex" % pattern,
                 SyntaxWarning, stacklevel=2)
             raise
 
         self.name = _ustr(self)
         self.errmsg = "Expected " + self.name
-        self.myException.msg = self.errmsg
+        #self.myException.msg = self.errmsg
         self.mayIndexError = False
         self.mayReturnEmpty = True
-    
+
     def parseImpl( self, instring, loc, doActions=True ):
         result = self.re.match(instring,loc)
         if not result:
             exc.loc = loc
             exc.pstr = instring
             raise exc
-        
+
         loc = result.end()
         d = result.groupdict()
         ret = ParseResults(result.group())
         if d:
-            for k in d.keys():
+            for k in d:
                 ret[k] = d[k]
         return loc,ret
-    
+
     def __str__( self ):
         try:
             return super(Regex,self).__str__()
         except:
             pass
-        
+
         if self.strRepr is None:
             self.strRepr = "Re:(%s)" % repr(self.pattern)
-        
+
         return self.strRepr
 
 
 class QuotedString(Token):
     """Token for matching strings that are delimited by quoting characters.
     """
-    def __init__( self, quoteChar, escChar=None, escQuote=None, multiline=False, unquoteResults=True):
+    def __init__( self, quoteChar, escChar=None, escQuote=None, multiline=False, unquoteResults=True, endQuoteChar=None):
         """
            Defined with the following parameters:
-           - quoteCharacter - string of one or more characters defining the quote delimiting string
-           - escapeCharacter - character to escape quotes, typically backslash (default=None)
-           - escapedQuote - special quote sequence to escape an embedded quote string (such as SQL's "" to escape and embedded ") (default=None)
-           - multiline - boolean indicating whether quotes can span multiple lines (default=False)
-           - unquoteResults - boolean indicating whether the matched text should be unquoted (default=True)
+            - quoteChar - string of one or more characters defining the quote delimiting string
+            - escChar - character to escape quotes, typically backslash (default=None)
+            - escQuote - special quote sequence to escape an embedded quote string (such as SQL's "" to escape an embedded ") (default=None)
+            - multiline - boolean indicating whether quotes can span multiple lines (default=False)
+            - unquoteResults - boolean indicating whether the matched text should be unquoted (default=True)
+            - endQuoteChar - string of one or more characters defining the end of the quote delimited string (default=None => same as quoteChar)
         """
         super(QuotedString,self).__init__()
-        
-        # remove white space from quote char - wont work anyway
+
+        # remove white space from quote chars - wont work anyway
         quoteChar = quoteChar.strip()
         if len(quoteChar) == 0:
             warnings.warn("quoteChar cannot be the empty string",SyntaxWarning,stacklevel=2)
             raise SyntaxError()
-        
+
+        if endQuoteChar is None:
+            endQuoteChar = quoteChar
+        else:
+            endQuoteChar = endQuoteChar.strip()
+            if len(endQuoteChar) == 0:
+                warnings.warn("endQuoteChar cannot be the empty string",SyntaxWarning,stacklevel=2)
+                raise SyntaxError()
+
         self.quoteChar = quoteChar
         self.quoteCharLen = len(quoteChar)
         self.firstQuoteChar = quoteChar[0]
+        self.endQuoteChar = endQuoteChar
+        self.endQuoteCharLen = len(endQuoteChar)
         self.escChar = escChar
         self.escQuote = escQuote
         self.unquoteResults = unquoteResults
-        
+
         if multiline:
             self.flags = re.MULTILINE | re.DOTALL
-            self.pattern = r'%s([^%s%s]' % \
+            self.pattern = r'%s(?:[^%s%s]' % \
                 ( re.escape(self.quoteChar),
-                  _escapeRegexRangeChars(self.quoteChar[0]),
+                  _escapeRegexRangeChars(self.endQuoteChar[0]),
                   (escChar is not None and _escapeRegexRangeChars(escChar) or '') )
         else:
             self.flags = 0
-            self.pattern = r'%s([^%s\n\r%s]' % \
+            self.pattern = r'%s(?:[^%s\n\r%s]' % \
                 ( re.escape(self.quoteChar),
-                  _escapeRegexRangeChars(self.quoteChar[0]),
+                  _escapeRegexRangeChars(self.endQuoteChar[0]),
                   (escChar is not None and _escapeRegexRangeChars(escChar) or '') )
-        if len(self.quoteChar) > 1:
+        if len(self.endQuoteChar) > 1:
             self.pattern += (
-                '|(' + ')|('.join(["%s[^%s]" % (re.escape(self.quoteChar[:i]),
-                                               _escapeRegexRangeChars(self.quoteChar[i])) 
-                                    for i in range(len(self.quoteChar)-1,0,-1)]) + ')'
+                '|(?:' + ')|(?:'.join(["%s[^%s]" % (re.escape(self.endQuoteChar[:i]),
+                                               _escapeRegexRangeChars(self.endQuoteChar[i]))
+                                    for i in range(len(self.endQuoteChar)-1,0,-1)]) + ')'
                 )
         if escQuote:
-            self.pattern += (r'|(%s)' % re.escape(escQuote))
+            self.pattern += (r'|(?:%s)' % re.escape(escQuote))
         if escChar:
-            self.pattern += (r'|(%s.)' % re.escape(escChar))
+            self.pattern += (r'|(?:%s.)' % re.escape(escChar))
             self.escCharReplacePattern = re.escape(self.escChar)+"(.)"
-        self.pattern += (r')*%s' % re.escape(self.quoteChar))
-        
+        self.pattern += (r')*%s' % re.escape(self.endQuoteChar))
+
         try:
             self.re = re.compile(self.pattern, self.flags)
             self.reString = self.pattern
-        except Exception,e:
-            warnings.warn("invalid pattern (%s) passed to Regex" % self.pattern, 
+        except sre_constants.error:
+            warnings.warn("invalid pattern (%s) passed to Regex" % self.pattern,
                 SyntaxWarning, stacklevel=2)
             raise
 
         self.name = _ustr(self)
         self.errmsg = "Expected " + self.name
-        self.myException.msg = self.errmsg
+        #self.myException.msg = self.errmsg
         self.mayIndexError = False
         self.mayReturnEmpty = True
-    
+
     def parseImpl( self, instring, loc, doActions=True ):
         result = instring[loc] == self.firstQuoteChar and self.re.match(instring,loc) or None
         if not result:
             exc.loc = loc
             exc.pstr = instring
             raise exc
-        
+
         loc = result.end()
         ret = result.group()
-        
+
         if self.unquoteResults:
-            
+
             # strip off quotes
-            ret = ret[self.quoteCharLen:-self.quoteCharLen]
-                
+            ret = ret[self.quoteCharLen:-self.endQuoteCharLen]
+
             if isinstance(ret,basestring):
                 # replace escaped characters
                 if self.escChar:
 
                 # replace escaped quotes
                 if self.escQuote:
-                    ret = ret.replace(self.escQuote, self.quoteChar)
+                    ret = ret.replace(self.escQuote, self.endQuoteChar)
 
         return loc, ret
-    
+
     def __str__( self ):
         try:
             return super(QuotedString,self).__str__()
         except:
             pass
-        
+
         if self.strRepr is None:
-            self.strRepr = "quoted string, delimited by %s characters" % self.quoteChar
-        
+            self.strRepr = "quoted string, starting with %s ending with %s" % (self.quoteChar, self.endQuoteChar)
+
         return self.strRepr
 
 
 class CharsNotIn(Token):
     """Token for matching words composed of characters *not* in a given set.
-       Defined with string containing all disallowed characters, and an optional 
-       minimum, maximum, and/or exact length.
+       Defined with string containing all disallowed characters, and an optional
+       minimum, maximum, and/or exact length.  The default value for min is 1 (a
+       minimum value < 1 is not valid); the default values for max and exact
+       are 0, meaning no maximum or exact length restriction.
     """
     def __init__( self, notChars, min=1, max=0, exact=0 ):
         super(CharsNotIn,self).__init__()
         self.skipWhitespace = False
         self.notChars = notChars
-        
+
+        if min < 1:
+            raise ValueError("cannot specify a minimum length < 1; use Optional(CharsNotIn()) if zero-length char group is permitted")
+
         self.minLen = min
 
         if max > 0:
             self.maxLen = max
         else:
-            self.maxLen = sys.maxint
+            self.maxLen = _MAX_INT
 
         if exact > 0:
             self.maxLen = exact
             self.minLen = exact
-        
+
         self.name = _ustr(self)
         self.errmsg = "Expected " + self.name
         self.mayReturnEmpty = ( self.minLen == 0 )
-        self.myException.msg = self.errmsg
+        #self.myException.msg = self.errmsg
         self.mayIndexError = False
 
     def parseImpl( self, instring, loc, doActions=True ):
         if instring[loc] in self.notChars:
-            #~ raise ParseException, ( instring, loc, self.errmsg )
+            #~ raise ParseException( instring, loc, self.errmsg )
             exc = self.myException
             exc.loc = loc
             exc.pstr = instring
             raise exc
-            
+
         start = loc
         loc += 1
         notchars = self.notChars
             loc += 1
 
         if loc - start < self.minLen:
-            #~ raise ParseException, ( instring, loc, self.errmsg )
+            #~ raise ParseException( instring, loc, self.errmsg )
             exc = self.myException
             exc.loc = loc
             exc.pstr = instring
                 self.strRepr = "!W:(%s...)" % self.notChars[:4]
             else:
                 self.strRepr = "!W:(%s)" % self.notChars
-        
+
         return self.strRepr
 
 class White(Token):
     def __init__(self, ws=" \t\r\n", min=1, max=0, exact=0):
         super(White,self).__init__()