109 lines
4.2 KiB
Python
109 lines
4.2 KiB
Python
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#! /usr/bin/env python3
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from __future__ import print_function
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import re
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try:
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basestring
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except NameError:
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basestring = str
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# ---------------------------------------------------------- Regex Match()
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# beware, stupid python interprets backslashes in replace-parts only partially!
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class MatchReplace:
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""" A MatchReplace is a mix of a Python Pattern and a Replace-Template """
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def __init__(self, matching, template, count = 0, flags = None):
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""" setup a substition from regex 'matching' into 'template',
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the replacement count default of 0 will replace all occurrences.
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The first argument may be a Match object or it is a string that
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will be turned into one by using Match(matching, flags). """
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self.template = template
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MatchReplace.__call__(self, matching, template, count, flags)
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def __call__(self, matching, template = None, count = 0, flags = None):
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""" other than __init__ the template may be left off to be unchanged"""
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if isinstance(count, basestring): # count/flags swapped over?
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flags = count; count = 0
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if isinstance(matching, Match):
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self.matching = matching
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else:
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self.matching = Match()(matching, flags) ## python 2.4.2 bug
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if template is not None:
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self.template = template
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self.count = count
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def __and__(self, string):
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""" z = MatchReplace('foo', 'bar') & 'foo'; assert z = 'bar' """
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text, self.matching.replaced = \
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self.matching.regex.subn(self.template, string, self.count)
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return text
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def __rand__(self, string):
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""" z = 'foo' & Match('foo') >> 'bar'; assert z = 'bar' """
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text, self.matching.replaced = \
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self.matching.regex.subn(self.template, string, self.count)
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return text
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def __iand__(self, string):
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""" x = 'foo' ; x &= Match('foo') >> 'bar'; assert x == 'bar' """
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string, self.matching.replaced = \
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self.matching.regex.subn(self.template, string, self.count)
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return string
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def __rshift__(self, count):
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" shorthand to set the replacement count: Match('foo') >> 'bar' >> 1 "
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self.count = count ; return self
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def __rlshift__(self, count):
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self.count = count ; return self
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class Match:
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""" A Match is actually a mix of a Python Pattern and MatchObject """
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def __init__(self, pattern = None, flags = None):
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""" flags is a string: 'i' for case-insensitive etc.; it is just
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short for a regex prefix: Match('foo','i') == Match('(?i)foo') """
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Match.__call__(self, pattern, flags)
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def __call__(self, pattern, flags = None):
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assert isinstance(pattern, str) or pattern is None
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assert isinstance(flags, str) or flags is None
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self.replaced = 0 # set by subn() inside MatchReplace
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self.found = None # set by search() to a MatchObject
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self.pattern = pattern
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if pattern is not None:
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if flags:
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self.regex = re.compile("(?"+flags+")"+self.pattern)
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else:
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self.regex = re.compile(self.pattern)
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return self
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def __repr__(self):
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return self.pattern
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def __truth__(self):
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return self.found is not None
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def __and__(self, string):
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self.found = self.regex.search(string)
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return self.__truth__()
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def __rand__(self, string):
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self.found = self.regex.search(string)
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return self.__truth__()
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def __rshift__(self, template):
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return MatchReplace(self, template)
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def __rlshift__(self, template):
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return MatchReplace(self, template)
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def __getitem__(self, index):
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return self.group(index)
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def group(self, index):
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assert self.found is not None
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return self.found.group(index)
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def finditer(self, string):
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return self.regex.finditer(string)
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if __name__ == "__main__":
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# matching:
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if "foo" & Match("oo"):
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print("oo")
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x = Match()
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if "foo" & x("(o+)"):
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print(x[1])
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# replacing:
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y = "fooboo" & Match("oo") >> "ee"
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print(y)
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r = Match("oo") >> "ee"
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print("fooboo" & r)
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s = MatchReplace("oo", "ee")
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print("fooboo" & s)
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