diff options
Diffstat (limited to 'Lib/re.py')
| -rw-r--r-- | Lib/re.py | 89 |
1 files changed, 52 insertions, 37 deletions
@@ -60,6 +60,7 @@ def valid_identifier(id): _cache = {} _MAXCACHE = 20 + def _cachecompile(pattern, flags): key = (pattern, flags) try: @@ -74,16 +75,16 @@ def _cachecompile(pattern, flags): def match(pattern, string, flags=0): return _cachecompile(pattern, flags).match(string) - + def search(pattern, string, flags=0): return _cachecompile(pattern, flags).search(string) - + def sub(pattern, repl, string, count=0): return _cachecompile(pattern).sub(repl, string, count) def subn(pattern, repl, string, count=0): return _cachecompile(pattern).subn(repl, string, count) - + def split(pattern, string, maxsplit=0): return _cachecompile(pattern).subn(string, maxsplit) @@ -100,12 +101,16 @@ class RegexObject: self.groupindex = groupindex self.callouts = callouts self.fastmap = build_fastmap(code) + if code[0].name == 'bol': self.anchor = 1 + elif code[0].name == 'begbuf': self.anchor = 2 + else: self.anchor = 0 + self.buffer = assemble(code) def search(self, string, pos=0): regs = reop.search(self.buffer, @@ -118,10 +123,12 @@ class RegexObject: pos) if regs is None: return None + return MatchObject(self, string, pos, regs) + def match(self, string, pos=0): regs = reop.match(self.buffer, self.num_regs, @@ -133,14 +140,18 @@ class RegexObject: pos) if regs is None: return None + return MatchObject(self, string, pos, regs) + def sub(self, repl, string, count=0): pass + def subn(self, repl, string, count=0): pass + def split(self, string, maxsplit=0): pass @@ -150,6 +161,7 @@ class MatchObject: self.string = string self.pos = pos self.regs = regs + def start(self, g): if type(g) == type(''): try: @@ -157,6 +169,7 @@ class MatchObject: except (KeyError, TypeError): raise IndexError, ('group "' + g + '" is undefined') return self.regs[g][0] + def end(self, g): if type(g) == type(''): try: @@ -164,6 +177,7 @@ class MatchObject: except (KeyError, TypeError): raise IndexError, ('group "' + g + '" is undefined') return self.regs[g][1] + def span(self, g): if type(g) == type(''): try: @@ -171,6 +185,7 @@ class MatchObject: except (KeyError, TypeError): raise IndexError, ('group "' + g + '" is undefined') return self.regs[g] + def group(self, *groups): if len(groups) == 0: groups = range(1, self.re.num_regs) @@ -339,7 +354,7 @@ class UpdateFailureJump(JumpInstruction): JumpInstruction.__init__(self, chr(12), label) class DummyFailureJump(JumpInstruction): - name = 'update_failure_jump' + name = 'dummy_failure_jump' def __init__(self, label): JumpInstruction.__init__(self, chr(13), label) @@ -764,11 +779,34 @@ def expand_escape(pattern, index, context=NORMAL): def compile(pattern, flags=0): stack = [] - index = 0 label = 0 register = 1 groupindex = {} callouts = [] + + # preprocess the pattern looking for embedded pattern modifiers + + index = 0 + while (index != -1): + index = string.find(pattern, '(?', index) + if index != -1: + index = index + 2 + if (index < len(pattern)) and (pattern[index] in 'iImMsSxX'): + while (index < len(pattern)) and (pattern[index] != ')'): + if pattern[index] in 'iI': + flags = flags | IGNORECASE + elif pattern[index] in 'mM': + flags = flags | MULTILINE + elif pattern[index] in 'sS': + flags = flags | DOTALL + elif pattern[index] in 'xX': + flags = flags | VERBOSE + else: + raise error, 'unknown flag' + index = index + 1 + + index = 0 + while (index < len(pattern)): char = pattern[index] index = index + 1 @@ -809,12 +847,6 @@ def compile(pattern, flags=0): raise error, 'unknown escape type' elif char == '|': - if len(stack) == 0: - raise error, 'alternate with nothing on the left' - if stack[-1][0].name == '(': - raise error, 'alternate with nothing on the left in the group' - if stack[-1][0].name == '|': - raise error, 'alternates with nothing inbetween them' expr = [] while (len(stack) != 0) and \ @@ -915,17 +947,10 @@ def compile(pattern, flags=0): 'assertion is unsupported') elif pattern[index] in 'iImMsSxX': + # ignore embedded pattern modifiers here, they + # have already been taken care of in the + # preprocessing while (index < len(pattern)) and (pattern[index] != ')'): - if pattern[index] in 'iI': - flags = flags | IGNORECASE - elif pattern[index] in 'mM': - flags = flags | MULTILINE - elif pattern[index] in 'sS': - flags = flags | DOTALL - elif pattern[index] in 'xX': - flags = flags | VERBOSE - else: - raise error, 'unknown flag' index = index + 1 index = index + 1 @@ -947,13 +972,6 @@ def compile(pattern, flags=0): if len(stack) == 0: raise error, 'too many close parens' - if len(expr) == 0: - raise error, 'nothing inside parens' - - # check to see if alternation used correctly - if (expr[-1].name == '|'): - raise error, 'alternate with nothing on the right' - # remove markers left by alternation expr = filter(lambda x: x.name != '|', expr) @@ -1023,18 +1041,17 @@ def compile(pattern, flags=0): while min > 0: expr = expr + stack[-1] min = min - 1 - registers = registers_used(stack[-1]) if minimal: expr = expr + \ ([Jump(label + 1), Label(label)] + \ stack[-1] + \ [Label(label + 1), - FailureJump(label, registers)]) + FailureJump(label)]) else: expr = expr + \ ([Label(label), - FailureJump(label + 1, registers)] + + FailureJump(label + 1)] + stack[-1] + [StarJump(label), Label(label + 1)]) @@ -1109,7 +1126,7 @@ def compile(pattern, flags=0): registers = registers_used(stack[-1]) if (index < len(pattern)) and (pattern[index] == '?'): # non-greedy matching - expr = [JumpInstructions(label + 1), + expr = [Jump(label + 1), Label(label)] + \ stack[-1] + \ [Label(label + 1), @@ -1130,9 +1147,10 @@ def compile(pattern, flags=0): # positive closure if len(stack) == 0: raise error, '+ needs something to repeat' + if (stack[-1][0].name == '(') or (stack[-1][0].name == '|'): raise error, '+ needs something to repeat' - registers = registers_used(stack[-1]) + if (index < len(pattern)) and (pattern[index] == '?'): # non-greedy expr = [Label(label)] + \ @@ -1156,7 +1174,6 @@ def compile(pattern, flags=0): elif char == '?': if len(stack) == 0: raise error, 'need something to be optional' - registers = registers_used(stack[-1]) if (index < len(pattern)) and (pattern[index] == '?'): # non-greedy matching expr = [FailureJump(label), @@ -1177,7 +1194,7 @@ def compile(pattern, flags=0): elif char == '.': if flags & DOTALL: - stack.append(Set(map(chr, range(256)))) + stack.append([Set(map(chr, range(256)))]) else: stack.append([AnyChar()]) @@ -1337,8 +1354,6 @@ def compile(pattern, flags=0): del stack[-1] if len(code) == 0: raise error, 'no code generated' - if (code[-1].name == '|'): - raise error, 'alternate with nothing on the right' code = filter(lambda x: x.name != '|', code) need_label = 0 for i in range(len(code)): |