[Python-checkins] CVS: python/dist/src/Lib sre_parse.py,1.3,1.4

A.M. Kuchling python-dev@python.org
Fri, 9 Jun 2000 07:08:11 -0700


Update of /cvsroot/python/python/dist/src/Lib
In directory slayer.i.sourceforge.net:/tmp/cvs-serv19644

Modified Files:
	sre_parse.py 
Log Message:
Patch from /F: this patch brings the CVS version of SRE in sync with the
latest public snapshot.""


Index: sre_parse.py
===================================================================
RCS file: /cvsroot/python/python/dist/src/Lib/sre_parse.py,v
retrieving revision 1.3
retrieving revision 1.4
diff -C2 -r1.3 -r1.4
*** sre_parse.py	2000/04/10 17:10:48	1.3
--- sre_parse.py	2000/06/09 14:08:07	1.4
***************
*** 3,9 ****
  # $Id$
  #
! # convert re-style regular expression to SRE template.  the current
! # implementation is somewhat incomplete, and not very fast.  should
! # definitely be rewritten before Python 1.6 goes beta.
  #
  # Copyright (c) 1998-2000 by Secret Labs AB.  All rights reserved.
--- 3,7 ----
  # $Id$
  #
! # convert re-style regular expression to sre pattern
  #
  # Copyright (c) 1998-2000 by Secret Labs AB.  All rights reserved.
***************
*** 17,27 ****
  #
  
- # FIXME: comments marked with the FIXME tag are open issues.  all such
- # issues should be closed before the final beta.
- 
  import string, sys
  
  from sre_constants import *
  
  SPECIAL_CHARS = ".\\[{()*+?^$|"
  REPEAT_CHARS  = "*+?{"
--- 15,28 ----
  #
  
  import string, sys
  
+ import _sre
+ 
  from sre_constants import *
  
+ # FIXME: should be 65535, but the array module currently chokes on
+ # unsigned integers larger than 32767...
+ MAXREPEAT = int(2L**(_sre.getcodesize()*8-1))-1
+ 
  SPECIAL_CHARS = ".\\[{()*+?^$|"
  REPEAT_CHARS  = "*+?{"
***************
*** 33,36 ****
--- 34,39 ----
  HEXDIGITS = tuple("0123456789abcdefABCDEF")
  
+ WHITESPACE = tuple(string.whitespace)
+ 
  ESCAPES = {
      "\\a": (LITERAL, chr(7)),
***************
*** 56,63 ****
  }
  
! class Pattern:
!     # FIXME: <fl> rename class, and store flags in here too!
      def __init__(self):
! 	self.flags = []
  	self.groups = 1
  	self.groupdict = {}
--- 59,74 ----
  }
  
! FLAGS = {
!     "i": SRE_FLAG_IGNORECASE,
!     "L": SRE_FLAG_LOCALE,
!     "m": SRE_FLAG_MULTILINE,
!     "s": SRE_FLAG_DOTALL,
!     "t": SRE_FLAG_TEMPLATE,
!     "x": SRE_FLAG_VERBOSE,
! }
! 
! class State:
      def __init__(self):
! 	self.flags = 0
  	self.groups = 1
  	self.groupdict = {}
***************
*** 68,74 ****
  	    self.groupdict[name] = gid
  	return gid
-     def setflag(self, flag):
- 	if flag in self.flags:
- 	    self.flags.append(flag)
  
  class SubPattern:
--- 79,82 ----
***************
*** 79,83 ****
  	    data = []
  	self.data = data
- 	self.flags = []
  	self.width = None
      def __repr__(self):
--- 87,90 ----
***************
*** 122,127 ****
  	    elif op in (MIN_REPEAT, MAX_REPEAT):
  		i, j = av[2].getwidth()
! 		lo = lo + i * av[0]
! 		hi = hi + j * av[1]
  	    elif op in (ANY, RANGE, IN, LITERAL, NOT_LITERAL, CATEGORY):
  		lo = lo + 1
--- 129,134 ----
  	    elif op in (MIN_REPEAT, MAX_REPEAT):
  		i, j = av[2].getwidth()
! 		lo = lo + long(i) * av[0]
! 		hi = hi + long(j) * av[1]
  	    elif op in (ANY, RANGE, IN, LITERAL, NOT_LITERAL, CATEGORY):
  		lo = lo + 1
***************
*** 131,175 ****
  	self.width = int(min(lo, sys.maxint)), int(min(hi, sys.maxint))
  	return self.width
-     def set(self, flag):
- 	if not flag in self.flags:
- 	    self.flags.append(flag)
-     def reset(self, flag):
- 	if flag in self.flags:
- 	    self.flags.remove(flag)
  
  class Tokenizer:
      def __init__(self, string):
! 	self.string = list(string)
  	self.next = self.__next()
      def __next(self):
! 	if not self.string:
  	    return None
! 	char = self.string[0]
  	if char[0] == "\\":
  	    try:
! 		c = self.string[1]
  	    except IndexError:
  		raise SyntaxError, "bogus escape"
  	    char = char + c
! 	    try:
! 		if c == "x":
! 		    # hexadecimal constant
! 		    for i in xrange(2, sys.maxint):
! 			c = self.string[i]
! 			if str(c) not in HEXDIGITS:
! 			    break
! 			char = char + c
! 		elif str(c) in DIGITS:
! 		    # decimal (or octal) number
! 		    for i in xrange(2, sys.maxint):
! 			c = self.string[i]
! 			# FIXME: if larger than current number of
! 			# groups, interpret as an octal number 
! 			if str(c) not in DIGITS:
! 			    break
! 			char = char + c
! 	    except IndexError:
! 		pass # use what we've got this far
! 	del self.string[0:len(char)]
  	return char
      def match(self, char):
--- 138,158 ----
  	self.width = int(min(lo, sys.maxint)), int(min(hi, sys.maxint))
  	return self.width
  
  class Tokenizer:
      def __init__(self, string):
! 	self.index = 0
! 	self.string = string
  	self.next = self.__next()
      def __next(self):
! 	if self.index >= len(self.string):
  	    return None
! 	char = self.string[self.index]
  	if char[0] == "\\":
  	    try:
! 		c = self.string[self.index + 1]
  	    except IndexError:
  		raise SyntaxError, "bogus escape"
  	    char = char + c
! 	self.index = self.index + len(char)
  	return char
      def match(self, char):
***************
*** 188,221 ****
  	return this
  
! def _fixescape(escape, character_class=0):
!     # convert escape to (type, value)
!     if character_class:
! 	# inside a character class, we'll look in the character
! 	# escapes dictionary first
! 	code = ESCAPES.get(escape)
! 	if code:
! 	    return code
! 	code = CATEGORIES.get(escape)
!     else:
! 	code = CATEGORIES.get(escape)
! 	if code:
! 	    return code
! 	code = ESCAPES.get(escape)
      if code:
  	return code
-     if not character_class:
- 	try:
- 	    group = int(escape[1:])
- 	    # FIXME: only valid if group <= current number of groups
- 	    return GROUP, group
- 	except ValueError:
- 	    pass
      try:
  	if escape[1:2] == "x":
  	    escape = escape[2:]
! 	    return LITERAL, chr(int(escape[-2:], 16) & 0xff)
  	elif str(escape[1:2]) in DIGITS:
! 	    return LITERAL, chr(int(escape[1:], 8) & 0xff)
! 	elif len(escape) == 2:
  	    return LITERAL, escape[1]
      except ValueError:
--- 171,242 ----
  	return this
  
! def _group(escape, state):
!     # check if the escape string represents a valid group
!     try:
! 	group = int(escape[1:])
! 	if group and group < state.groups:
! 	    return group
!     except ValueError:
! 	pass
!     return None # not a valid group
! 
! def _class_escape(source, escape):
!     # handle escape code inside character class
!     code = ESCAPES.get(escape)
!     if code:
! 	return code
!     code = CATEGORIES.get(escape)
!     if code:
! 	return code
!     try:
! 	if escape[1:2] == "x":
! 	    while source.next in HEXDIGITS:
! 		escape = escape + source.get()
! 	    escape = escape[2:]
! 	    # FIXME: support unicode characters!
! 	    return LITERAL, chr(int(escape[-4:], 16) & 0xff)
! 	elif str(escape[1:2]) in OCTDIGITS:
! 	    while source.next in OCTDIGITS:
! 		escape = escape + source.get()
! 	    escape = escape[1:]
! 	    # FIXME: support unicode characters!
! 	    return LITERAL, chr(int(escape[-6:], 8) & 0xff)
! 	if len(escape) == 2:
! 	    return LITERAL, escape[1]
!     except ValueError:
! 	pass
!     raise SyntaxError, "bogus escape: %s" % repr(escape)
! 
! def _escape(source, escape, state):
!     # handle escape code in expression
!     code = CATEGORIES.get(escape)
!     if code:
! 	return code
!     code = ESCAPES.get(escape)
      if code:
  	return code
      try:
  	if escape[1:2] == "x":
+ 	    while source.next in HEXDIGITS:
+ 		escape = escape + source.get()
  	    escape = escape[2:]
! 	    # FIXME: support unicode characters!
! 	    return LITERAL, chr(int(escape[-4:], 16) & 0xff)
  	elif str(escape[1:2]) in DIGITS:
! 	    while 1:
! 		group = _group(escape, state)
! 		if group:
! 		    if (not source.next or
! 			not _group(escape + source.next, state)):
! 		        return GROUP, group
! 		    escape = escape + source.get()
! 		elif source.next in OCTDIGITS:
! 		    escape = escape + source.get()
! 		else:
! 		    break
! 	    escape = escape[1:]
! 	    # FIXME: support unicode characters!
! 	    return LITERAL, chr(int(escape[-6:], 8) & 0xff)
! 	if len(escape) == 2:
  	    return LITERAL, escape[1]
      except ValueError:
***************
*** 223,231 ****
      raise SyntaxError, "bogus escape: %s" % repr(escape)
  
- def _branch(subpattern, items):
  
      # form a branch operator from a set of items (FIXME: move this
      # optimization to the compiler module!)
  
      # check if all items share a common prefix
      while 1:
--- 244,255 ----
      raise SyntaxError, "bogus escape: %s" % repr(escape)
  
  
+ def _branch(pattern, items):
+ 
      # form a branch operator from a set of items (FIXME: move this
      # optimization to the compiler module!)
  
+     subpattern = SubPattern(pattern)
+ 
      # check if all items share a common prefix
      while 1:
***************
*** 258,272 ****
  	    set.append(item[0])
  	subpattern.append((IN, set))
! 	return
  
      subpattern.append((BRANCH, (None, items)))
  
! def _parse(source, pattern, flags=()):
  
      # parse regular expression pattern into an operator list.
- 
-     subpattern = SubPattern(pattern)
  
!     this = None
  
      while 1:
--- 282,295 ----
  	    set.append(item[0])
  	subpattern.append((IN, set))
! 	return subpattern
  
      subpattern.append((BRANCH, (None, items)))
+     return subpattern
  
! def _parse(source, state, flags=0):
  
      # parse regular expression pattern into an operator list.
  
!     subpattern = SubPattern(state)
  
      while 1:
***************
*** 278,281 ****
--- 301,315 ----
  	    break # end of pattern
  
+ 	if state.flags & SRE_FLAG_VERBOSE:
+ 	    # skip whitespace and comments
+ 	    if this in WHITESPACE:
+ 		continue
+ 	    if this == "#":
+ 		while 1:
+ 		    this = source.get()
+ 		    if this in (None, "\n"):
+ 			break
+ 		continue
+ 
  	if this and this[0] not in SPECIAL_CHARS:
  	    subpattern.append((LITERAL, this))
***************
*** 295,299 ****
  		    break
  		elif this and this[0] == "\\":
! 		    code1 = _fixescape(this, 1)
  		elif this:
  		    code1 = LITERAL, this
--- 329,333 ----
  		    break
  		elif this and this[0] == "\\":
! 		    code1 = _class_escape(source, this)
  		elif this:
  		    code1 = LITERAL, this
***************
*** 309,313 ****
  		    else:
  			if this[0] == "\\":
! 			    code2 = _fixescape(this, 1)
  			else:
  			    code2 = LITERAL, this
--- 343,347 ----
  		    else:
  			if this[0] == "\\":
! 			    code2 = _class_escape(source, this)
  			else:
  			    code2 = LITERAL, this
***************
*** 322,326 ****
  		    set.append(code1)
  
! 	    # FIXME: <fl> move set optimization to support function
  	    if len(set)==1 and set[0][0] is LITERAL:
  		subpattern.append(set[0]) # optimization
--- 356,360 ----
  		    set.append(code1)
  
! 	    # FIXME: <fl> move set optimization to compiler!
  	    if len(set)==1 and set[0][0] is LITERAL:
  		subpattern.append(set[0]) # optimization
***************
*** 336,344 ****
  		min, max = 0, 1
  	    elif this == "*":
! 		min, max = 0, sys.maxint
  	    elif this == "+":
! 		min, max = 1, sys.maxint
  	    elif this == "{":
! 		min, max = 0, sys.maxint
  		lo = hi = ""
  		while str(source.next) in DIGITS:
--- 370,378 ----
  		min, max = 0, 1
  	    elif this == "*":
! 		min, max = 0, MAXREPEAT
  	    elif this == "+":
! 		min, max = 1, MAXREPEAT
  	    elif this == "{":
! 		min, max = 0, MAXREPEAT
  		lo = hi = ""
  		while str(source.next) in DIGITS:
***************
*** 359,376 ****
  		raise SyntaxError, "not supported"
  	    # figure out which item to repeat
- 	    # FIXME: should back up to the right mark, right?
  	    if subpattern:
! 		index = len(subpattern)-1
! 		while subpattern[index][0] is MARK:
! 		    index = index - 1
! 		item = subpattern[index:index+1]
  	    else:
  		raise SyntaxError, "nothing to repeat"
  	    if source.match("?"):
! 		subpattern[index] = (MIN_REPEAT, (min, max, item))
  	    else:
! 		subpattern[index] = (MAX_REPEAT, (min, max, item))
  	elif this == ".":
  	    subpattern.append((ANY, None))
  	elif this == "(":
  	    group = 1
--- 393,408 ----
  		raise SyntaxError, "not supported"
  	    # figure out which item to repeat
  	    if subpattern:
! 		item = subpattern[-1:]
  	    else:
  		raise SyntaxError, "nothing to repeat"
  	    if source.match("?"):
! 		subpattern[-1] = (MIN_REPEAT, (min, max, item))
  	    else:
! 		subpattern[-1] = (MAX_REPEAT, (min, max, item))
! 
  	elif this == ".":
  	    subpattern.append((ANY, None))
+ 
  	elif this == "(":
  	    group = 1
***************
*** 380,405 ****
  		# options
  		if source.match("P"):
! 		    # named group: skip forward to end of name
  		    if source.match("<"):
  			name = ""
  			while 1:
  			    char = source.get()
! 			    if char is None or char == ">":
  				break
  			    name = name + char
  			group = 1
  		elif source.match(":"):
  		    # non-capturing group
  		    group = 2
! 		elif source.match_set("iI"):
! 		    pattern.setflag("i")
! 		elif source.match_set("lL"):
! 		    pattern.setflag("l")
! 		elif source.match_set("mM"):
! 		    pattern.setflag("m")
! 		elif source.match_set("sS"):
! 		    pattern.setflag("s")
! 		elif source.match_set("xX"):
! 		    pattern.setflag("x")
  	    if group:
  		# parse group contents
--- 412,450 ----
  		# options
  		if source.match("P"):
! 		    # python extensions
  		    if source.match("<"):
+ 			# named group: skip forward to end of name
  			name = ""
  			while 1:
  			    char = source.get()
! 			    if char is None:
! 				raise SyntaxError, "unterminated name"
! 			    if char == ">":
  				break
+ 			    # FIXME: check for valid character
  			    name = name + char
  			group = 1
+ 		    elif source.match("="):
+ 			# named backreference
+ 			raise SyntaxError, "not yet implemented"
+ 
+ 		    else:
+ 			char = source.get()
+ 			if char is None:
+ 			    raise SyntaxError, "unexpected end of pattern"
+ 			raise SyntaxError, "unknown specifier: ?P%s" % char
  		elif source.match(":"):
  		    # non-capturing group
  		    group = 2
! 		elif source.match("#"):
! 		    # comment
! 		    while 1:
! 			char = source.get()
! 			if char is None or char == ")":
! 			    break
! 		else:
! 		    # flags
! 		    while FLAGS.has_key(source.next):
! 			state.flags = state.flags | FLAGS[source.get()]
  	    if group:
  		# parse group contents
***************
*** 409,423 ****
  		    group = None
  		else:
! 		    group = pattern.getgroup(name)
!  		if group:
!  		    subpattern.append((MARK, (group-1)*2))
  		while 1:
! 		    p = _parse(source, pattern, flags)
  		    if source.match(")"):
  			if b:
  			    b.append(p)
! 			    _branch(subpattern, b)
! 			else:
! 			    subpattern.append((SUBPATTERN, (group, p)))
  			break
  		    elif source.match("|"):
--- 454,465 ----
  		    group = None
  		else:
! 		    group = state.getgroup(name)
  		while 1:
! 		    p = _parse(source, state, flags)
  		    if source.match(")"):
  			if b:
  			    b.append(p)
! 			    p = _branch(state, b)
! 			subpattern.append((SUBPATTERN, (group, p)))
  			break
  		    elif source.match("|"):
***************
*** 425,436 ****
  		    else:
  			raise SyntaxError, "group not properly closed"
-  		if group:
-  		    subpattern.append((MARK, (group-1)*2+1))
  	    else:
- 		# FIXME: should this really be a while loop?
  		while 1:
  		    char = source.get()
  		    if char is None or char == ")":
  			break
  
  	elif this == "^":
--- 467,476 ----
  		    else:
  			raise SyntaxError, "group not properly closed"
  	    else:
  		while 1:
  		    char = source.get()
  		    if char is None or char == ")":
  			break
+ 		# FIXME: skip characters?
  
  	elif this == "^":
***************
*** 441,445 ****
  
  	elif this and this[0] == "\\":
! 	    code =_fixescape(this)
  	    subpattern.append(code)
  
--- 481,485 ----
  
  	elif this and this[0] == "\\":
! 	    code = _escape(source, this, state)
  	    subpattern.append(code)
  
***************
*** 449,459 ****
      return subpattern
  
! def parse(source, flags=()):
!     s = Tokenizer(source)
!     g = Pattern()
      b = []
      while 1:
! 	p = _parse(s, g, flags)
! 	tail = s.get()
  	if tail == "|":
  	    b.append(p)
--- 489,500 ----
      return subpattern
  
! def parse(pattern, flags=0):
!     # parse 're' pattern into list of (opcode, argument) tuples
!     source = Tokenizer(pattern)
!     state = State()
      b = []
      while 1:
! 	p = _parse(source, state, flags)
! 	tail = source.get()
  	if tail == "|":
  	    b.append(p)
***************
*** 463,471 ****
  	    if b:
  		b.append(p)
! 		p = SubPattern(g)
! 		_branch(p, b)
  	    break
  	else:
  	    raise SyntaxError, "bogus characters at end of regular expression"
      return p
  
--- 504,531 ----
  	    if b:
  		b.append(p)
! 		p = _branch(state, b)
  	    break
  	else:
  	    raise SyntaxError, "bogus characters at end of regular expression"
+     return p
+ 
+ def parse_replacement(source, pattern):
+     # parse 're' replacement string into list of literals and
+     # group references
+     s = Tokenizer(source)
+     p = []
+     a = p.append
+     while 1:
+ 	this = s.get()
+ 	if this is None:
+ 	    break # end of replacement string
+ 	if this and this[0] == "\\":
+ 	    try:
+ 		a(LITERAL, ESCAPES[this])
+ 	    except KeyError:
+ 		for char in this:
+ 		    a(LITERAL, char)
+ 	else:
+ 	    a(LITERAL, this)
      return p