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-rw-r--r--Lib/dos-8x3/sre_pars.py682
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diff --git a/Lib/dos-8x3/sre_pars.py b/Lib/dos-8x3/sre_pars.py
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--- a/Lib/dos-8x3/sre_pars.py
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@@ -1,682 +0,0 @@
-#
-# Secret Labs' Regular Expression Engine
-#
-# convert re-style regular expression to sre pattern
-#
-# Copyright (c) 1998-2000 by Secret Labs AB. All rights reserved.
-#
-# See the sre.py file for information on usage and redistribution.
-#
-
-import string, sys
-
-from sre_constants import *
-
-SPECIAL_CHARS = ".\\[{()*+?^$|"
-REPEAT_CHARS = "*+?{"
-
-DIGITS = tuple("0123456789")
-
-OCTDIGITS = tuple("01234567")
-HEXDIGITS = tuple("0123456789abcdefABCDEF")
-
-WHITESPACE = tuple(" \t\n\r\v\f")
-
-ESCAPES = {
- r"\a": (LITERAL, 7),
- r"\b": (LITERAL, 8),
- r"\f": (LITERAL, 12),
- r"\n": (LITERAL, 10),
- r"\r": (LITERAL, 13),
- r"\t": (LITERAL, 9),
- r"\v": (LITERAL, 11),
- r"\\": (LITERAL, ord("\\"))
-}
-
-CATEGORIES = {
- r"\A": (AT, AT_BEGINNING), # start of string
- r"\b": (AT, AT_BOUNDARY),
- r"\B": (AT, AT_NON_BOUNDARY),
- r"\d": (IN, [(CATEGORY, CATEGORY_DIGIT)]),
- r"\D": (IN, [(CATEGORY, CATEGORY_NOT_DIGIT)]),
- r"\s": (IN, [(CATEGORY, CATEGORY_SPACE)]),
- r"\S": (IN, [(CATEGORY, CATEGORY_NOT_SPACE)]),
- r"\w": (IN, [(CATEGORY, CATEGORY_WORD)]),
- r"\W": (IN, [(CATEGORY, CATEGORY_NOT_WORD)]),
- r"\Z": (AT, AT_END), # end of string
-}
-
-FLAGS = {
- # standard flags
- "i": SRE_FLAG_IGNORECASE,
- "L": SRE_FLAG_LOCALE,
- "m": SRE_FLAG_MULTILINE,
- "s": SRE_FLAG_DOTALL,
- "x": SRE_FLAG_VERBOSE,
- # extensions
- "t": SRE_FLAG_TEMPLATE,
- "u": SRE_FLAG_UNICODE,
-}
-
-class Pattern:
- # master pattern object. keeps track of global attributes
- def __init__(self):
- self.flags = 0
- self.groups = 1
- self.groupdict = {}
- def getgroup(self, name=None):
- gid = self.groups
- self.groups = gid + 1
- if name:
- self.groupdict[name] = gid
- return gid
-
-class SubPattern:
- # a subpattern, in intermediate form
- def __init__(self, pattern, data=None):
- self.pattern = pattern
- if not data:
- data = []
- self.data = data
- self.width = None
- def dump(self, level=0):
- nl = 1
- for op, av in self.data:
- print level*" " + op,; nl = 0
- if op == "in":
- # member sublanguage
- print; nl = 1
- for op, a in av:
- print (level+1)*" " + op, a
- elif op == "branch":
- print; nl = 1
- i = 0
- for a in av[1]:
- if i > 0:
- print level*" " + "or"
- a.dump(level+1); nl = 1
- i = i + 1
- elif type(av) in (type(()), type([])):
- for a in av:
- if isinstance(a, SubPattern):
- if not nl: print
- a.dump(level+1); nl = 1
- else:
- print a, ; nl = 0
- else:
- print av, ; nl = 0
- if not nl: print
- def __repr__(self):
- return repr(self.data)
- def __len__(self):
- return len(self.data)
- def __delitem__(self, index):
- del self.data[index]
- def __getitem__(self, index):
- return self.data[index]
- def __setitem__(self, index, code):
- self.data[index] = code
- def __getslice__(self, start, stop):
- return SubPattern(self.pattern, self.data[start:stop])
- def insert(self, index, code):
- self.data.insert(index, code)
- def append(self, code):
- self.data.append(code)
- def getwidth(self):
- # determine the width (min, max) for this subpattern
- if self.width:
- return self.width
- lo = hi = 0L
- for op, av in self.data:
- if op is BRANCH:
- i = sys.maxint
- j = 0
- for av in av[1]:
- l, h = av.getwidth()
- i = min(i, l)
- j = max(j, h)
- lo = lo + i
- hi = hi + j
- elif op is CALL:
- i, j = av.getwidth()
- lo = lo + i
- hi = hi + j
- elif op is SUBPATTERN:
- i, j = av[1].getwidth()
- lo = lo + i
- hi = hi + j
- 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
- hi = hi + 1
- elif op == SUCCESS:
- break
- self.width = int(min(lo, sys.maxint)), int(min(hi, sys.maxint))
- return self.width
-
-class Tokenizer:
- def __init__(self, string):
- self.string = string
- self.index = 0
- self.__next()
- def __next(self):
- if self.index >= len(self.string):
- self.next = None
- return
- char = self.string[self.index]
- if char[0] == "\\":
- try:
- c = self.string[self.index + 1]
- except IndexError:
- raise error, "bogus escape"
- char = char + c
- self.index = self.index + len(char)
- self.next = char
- def match(self, char, skip=1):
- if char == self.next:
- if skip:
- self.__next()
- return 1
- return 0
- def get(self):
- this = self.next
- self.__next()
- return this
- def tell(self):
- return self.index, self.next
- def seek(self, index):
- self.index, self.next = index
-
-def isident(char):
- return "a" <= char <= "z" or "A" <= char <= "Z" or char == "_"
-
-def isdigit(char):
- return "0" <= char <= "9"
-
-def isname(name):
- # check that group name is a valid string
- if not isident(name[0]):
- return 0
- for char in name:
- if not isident(char) and not isdigit(char):
- return 0
- return 1
-
-def _group(escape, groups):
- # check if the escape string represents a valid group
- try:
- gid = int(escape[1:])
- if gid and gid < groups:
- return gid
- 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":
- # hexadecimal escape (exactly two digits)
- while source.next in HEXDIGITS and len(escape) < 4:
- escape = escape + source.get()
- escape = escape[2:]
- if len(escape) != 2:
- raise error, "bogus escape: %s" % repr("\\" + escape)
- return LITERAL, int(escape, 16) & 0xff
- elif str(escape[1:2]) in OCTDIGITS:
- # octal escape (up to three digits)
- while source.next in OCTDIGITS and len(escape) < 5:
- escape = escape + source.get()
- escape = escape[1:]
- return LITERAL, int(escape, 8) & 0xff
- if len(escape) == 2:
- return LITERAL, ord(escape[1])
- except ValueError:
- pass
- raise error, "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":
- # hexadecimal escape
- while source.next in HEXDIGITS and len(escape) < 4:
- escape = escape + source.get()
- if len(escape) != 4:
- raise ValueError
- return LITERAL, int(escape[2:], 16) & 0xff
- elif escape[1:2] == "0":
- # octal escape
- while source.next in OCTDIGITS and len(escape) < 4:
- escape = escape + source.get()
- return LITERAL, int(escape[1:], 8) & 0xff
- elif escape[1:2] in DIGITS:
- # octal escape *or* decimal group reference (sigh)
- here = source.tell()
- if source.next in DIGITS:
- escape = escape + source.get()
- if (escape[1] in OCTDIGITS and escape[2] in OCTDIGITS and
- source.next in OCTDIGITS):
- # got three octal digits; this is an octal escape
- escape = escape + source.get()
- return LITERAL, int(escape[1:], 8) & 0xff
- # got at least one decimal digit; this is a group reference
- group = _group(escape, state.groups)
- if group:
- return GROUPREF, group
- raise ValueError
- if len(escape) == 2:
- return LITERAL, ord(escape[1])
- except ValueError:
- pass
- raise error, "bogus escape: %s" % repr(escape)
-
-def _parse_sub(source, state, nested=1):
- # parse an alternation: a|b|c
-
- items = []
- while 1:
- items.append(_parse(source, state))
- if source.match("|"):
- continue
- if not nested:
- break
- if not source.next or source.match(")", 0):
- break
- else:
- raise error, "pattern not properly closed"
-
- if len(items) == 1:
- return items[0]
-
- subpattern = SubPattern(state)
-
- # check if all items share a common prefix
- while 1:
- prefix = None
- for item in items:
- if not item:
- break
- if prefix is None:
- prefix = item[0]
- elif item[0] != prefix:
- break
- else:
- # all subitems start with a common "prefix".
- # move it out of the branch
- for item in items:
- del item[0]
- subpattern.append(prefix)
- continue # check next one
- break
-
- # check if the branch can be replaced by a character set
- for item in items:
- if len(item) != 1 or item[0][0] != LITERAL:
- break
- else:
- # we can store this as a character set instead of a
- # branch (the compiler may optimize this even more)
- set = []
- for item in items:
- set.append(item[0])
- subpattern.append((IN, set))
- return subpattern
-
- subpattern.append((BRANCH, (None, items)))
- return subpattern
-
-def _parse(source, state):
- # parse a simple pattern
-
- subpattern = SubPattern(state)
-
- while 1:
-
- if source.next in ("|", ")"):
- break # end of subpattern
- this = source.get()
- if this is None:
- 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, ord(this)))
-
- elif this == "[":
- # character set
- set = []
-## if source.match(":"):
-## pass # handle character classes
- if source.match("^"):
- set.append((NEGATE, None))
- # check remaining characters
- start = set[:]
- while 1:
- this = source.get()
- if this == "]" and set != start:
- break
- elif this and this[0] == "\\":
- code1 = _class_escape(source, this)
- elif this:
- code1 = LITERAL, ord(this)
- else:
- raise error, "unexpected end of regular expression"
- if source.match("-"):
- # potential range
- this = source.get()
- if this == "]":
- if code1[0] is IN:
- code1 = code1[1][0]
- set.append(code1)
- set.append((LITERAL, ord("-")))
- break
- else:
- if this[0] == "\\":
- code2 = _class_escape(source, this)
- else:
- code2 = LITERAL, ord(this)
- if code1[0] != LITERAL or code2[0] != LITERAL:
- raise error, "illegal range"
- lo = code1[1]
- hi = code2[1]
- if hi < lo:
- raise error, "illegal range"
- set.append((RANGE, (lo, hi)))
- else:
- if code1[0] is IN:
- code1 = code1[1][0]
- 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
- elif len(set)==2 and set[0][0] is NEGATE and set[1][0] is LITERAL:
- subpattern.append((NOT_LITERAL, set[1][1])) # optimization
- else:
- # FIXME: <fl> add charmap optimization
- subpattern.append((IN, set))
-
- elif this and this[0] in REPEAT_CHARS:
- # repeat previous item
- if this == "?":
- min, max = 0, 1
- elif this == "*":
- min, max = 0, MAXREPEAT
- elif this == "+":
- min, max = 1, MAXREPEAT
- elif this == "{":
- here = source.tell()
- min, max = 0, MAXREPEAT
- lo = hi = ""
- while source.next in DIGITS:
- lo = lo + source.get()
- if source.match(","):
- while source.next in DIGITS:
- hi = hi + source.get()
- else:
- hi = lo
- if not source.match("}"):
- subpattern.append((LITERAL, ord(this)))
- source.seek(here)
- continue
- if lo:
- min = int(lo)
- if hi:
- max = int(hi)
- # FIXME: <fl> check that hi >= lo!
- else:
- raise error, "not supported"
- # figure out which item to repeat
- if subpattern:
- item = subpattern[-1:]
- else:
- raise error, "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
- name = None
- if source.match("?"):
- group = 0
- # 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 error, "unterminated name"
- if char == ">":
- break
- name = name + char
- group = 1
- if not isname(name):
- raise error, "illegal character in group name"
- elif source.match("="):
- # named backreference
- name = ""
- while 1:
- char = source.get()
- if char is None:
- raise error, "unterminated name"
- if char == ")":
- break
- name = name + char
- if not isname(name):
- raise error, "illegal character in group name"
- gid = state.groupdict.get(name)
- if gid is None:
- raise error, "unknown group name"
- subpattern.append((GROUPREF, gid))
- continue
- else:
- char = source.get()
- if char is None:
- raise error, "unexpected end of pattern"
- raise error, "unknown specifier: ?P%s" % char
- elif source.match(":"):
- # non-capturing group
- group = 2
- elif source.match("#"):
- # comment
- while 1:
- if source.next is None or source.next == ")":
- break
- source.get()
- if not source.match(")"):
- raise error, "unbalanced parenthesis"
- continue
- elif source.next in ("=", "!", "<"):
- # lookahead assertions
- char = source.get()
- dir = 1
- if char == "<":
- if source.next not in ("=", "!"):
- raise error, "syntax error"
- dir = -1 # lookbehind
- char = source.get()
- p = _parse_sub(source, state)
- if not source.match(")"):
- raise error, "unbalanced parenthesis"
- if char == "=":
- subpattern.append((ASSERT, (dir, p)))
- else:
- subpattern.append((ASSERT_NOT, (dir, p)))
- continue
- else:
- # flags
- while FLAGS.has_key(source.next):
- state.flags = state.flags | FLAGS[source.get()]
- if group:
- # parse group contents
- if group == 2:
- # anonymous group
- group = None
- else:
- group = state.getgroup(name)
- p = _parse_sub(source, state)
- if not source.match(")"):
- raise error, "unbalanced parenthesis"
- subpattern.append((SUBPATTERN, (group, p)))
- else:
- while 1:
- char = source.get()
- if char is None or char == ")":
- break
- raise error, "unknown extension"
-
- elif this == "^":
- subpattern.append((AT, AT_BEGINNING))
-
- elif this == "$":
- subpattern.append((AT, AT_END))
-
- elif this and this[0] == "\\":
- code = _escape(source, this, state)
- subpattern.append(code)
-
- else:
- raise error, "parser error"
-
- return subpattern
-
-def parse(str, flags=0, pattern=None):
- # parse 're' pattern into list of (opcode, argument) tuples
-
- source = Tokenizer(str)
-
- if pattern is None:
- pattern = Pattern()
- pattern.flags = flags
-
- p = _parse_sub(source, pattern, 0)
-
- tail = source.get()
- if tail == ")":
- raise error, "unbalanced parenthesis"
- elif tail:
- raise error, "bogus characters at end of regular expression"
-
- # p.dump()
-
- if not (flags & SRE_FLAG_VERBOSE) and p.pattern.flags & SRE_FLAG_VERBOSE:
- # the VERBOSE flag was switched on inside the pattern. to be
- # on the safe side, we'll parse the whole thing again...
- return parse(str, p.pattern.flags)
-
- return p
-
-def parse_template(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] == "\\":
- # group
- if this == "\\g":
- name = ""
- if s.match("<"):
- while 1:
- char = s.get()
- if char is None:
- raise error, "unterminated group name"
- if char == ">":
- break
- name = name + char
- if not name:
- raise error, "bad group name"
- try:
- index = int(name)
- except ValueError:
- if not isname(name):
- raise error, "illegal character in group name"
- try:
- index = pattern.groupindex[name]
- except KeyError:
- raise IndexError, "unknown group name"
- a((MARK, index))
- elif len(this) > 1 and this[1] in DIGITS:
- code = None
- while 1:
- group = _group(this, pattern.groups+1)
- if group:
- if (s.next not in DIGITS or
- not _group(this + s.next, pattern.groups+1)):
- code = MARK, int(group)
- break
- elif s.next in OCTDIGITS:
- this = this + s.get()
- else:
- break
- if not code:
- this = this[1:]
- code = LITERAL, int(this[-6:], 8) & 0xff
- a(code)
- else:
- try:
- a(ESCAPES[this])
- except KeyError:
- for c in this:
- a((LITERAL, ord(c)))
- else:
- a((LITERAL, ord(this)))
- return p
-
-def expand_template(template, match):
- # FIXME: <fl> this is sooooo slow. drop in the slicelist
- # code instead
- p = []
- a = p.append
- sep = match.string[:0]
- if type(sep) is type(""):
- char = chr
- else:
- char = unichr
- for c, s in template:
- if c is LITERAL:
- a(char(s))
- elif c is MARK:
- s = match.group(s)
- if s is None:
- raise error, "empty group"
- a(s)
- return string.join(p, sep)