Issue #10875: Update Regular Expression HOWTO; patch by 'SilentGhost'.
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@ -5,7 +5,6 @@
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****************************
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:Author: A.M. Kuchling <amk@amk.ca>
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:Release: 0.05
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.. TODO:
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Document lookbehind assertions
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@ -264,7 +263,7 @@ performing string substitutions. ::
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>>> import re
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>>> p = re.compile('ab*')
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>>> print p
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<_sre.SRE_Pattern object at 80b4150>
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<_sre.SRE_Pattern object at 0x...>
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:func:`re.compile` also accepts an optional *flags* argument, used to enable
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various special features and syntax variations. We'll go over the available
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@ -377,7 +376,7 @@ Python interpreter, import the :mod:`re` module, and compile a RE::
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>>> import re
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>>> p = re.compile('[a-z]+')
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>>> p
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<_sre.SRE_Pattern object at 80c3c28>
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<_sre.SRE_Pattern object at 0x...>
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Now, you can try matching various strings against the RE ``[a-z]+``. An empty
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string shouldn't match at all, since ``+`` means 'one or more repetitions'.
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@ -395,7 +394,7 @@ result in a variable for later use. ::
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>>> m = p.match('tempo')
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>>> print m
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<_sre.SRE_Match object at 80c4f68>
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<_sre.SRE_Match object at 0x...>
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Now you can query the :class:`MatchObject` for information about the matching
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string. :class:`MatchObject` instances also have several methods and
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@ -434,7 +433,7 @@ case. ::
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>>> print p.match('::: message')
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None
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>>> m = p.search('::: message') ; print m
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<re.MatchObject instance at 80c9650>
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<_sre.SRE_Match object at 0x...>
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>>> m.group()
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'message'
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>>> m.span()
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@ -485,7 +484,7 @@ the RE string added as the first argument, and still return either ``None`` or a
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>>> print re.match(r'From\s+', 'Fromage amk')
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None
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>>> re.match(r'From\s+', 'From amk Thu May 14 19:12:10 1998')
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<re.MatchObject instance at 80c5978>
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<_sre.SRE_Match object at 0x...>
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Under the hood, these functions simply create a pattern object for you
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and call the appropriate method on it. They also store the compiled object in a
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@ -686,7 +685,7 @@ given location, they can obviously be matched an infinite number of times.
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line, the RE to use is ``^From``. ::
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>>> print re.search('^From', 'From Here to Eternity')
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<re.MatchObject instance at 80c1520>
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<_sre.SRE_Match object at 0x...>
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>>> print re.search('^From', 'Reciting From Memory')
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None
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@ -698,11 +697,11 @@ given location, they can obviously be matched an infinite number of times.
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or any location followed by a newline character. ::
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>>> print re.search('}$', '{block}')
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<re.MatchObject instance at 80adfa8>
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<_sre.SRE_Match object at 0x...>
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>>> print re.search('}$', '{block} ')
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None
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>>> print re.search('}$', '{block}\n')
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<re.MatchObject instance at 80adfa8>
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<_sre.SRE_Match object at 0x...>
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To match a literal ``'$'``, use ``\$`` or enclose it inside a character class,
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as in ``[$]``.
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@ -727,7 +726,7 @@ given location, they can obviously be matched an infinite number of times.
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>>> p = re.compile(r'\bclass\b')
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>>> print p.search('no class at all')
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<re.MatchObject instance at 80c8f28>
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<_sre.SRE_Match object at 0x...>
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>>> print p.search('the declassified algorithm')
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None
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>>> print p.search('one subclass is')
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@ -745,7 +744,7 @@ given location, they can obviously be matched an infinite number of times.
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>>> print p.search('no class at all')
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None
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>>> print p.search('\b' + 'class' + '\b')
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<re.MatchObject instance at 80c3ee0>
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<_sre.SRE_Match object at 0x...>
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Second, inside a character class, where there's no use for this assertion,
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``\b`` represents the backspace character, for compatibility with Python's
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@ -1315,7 +1314,7 @@ a regular expression that handles all of the possible cases, the patterns will
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be *very* complicated. Use an HTML or XML parser module for such tasks.)
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Not Using re.VERBOSE
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Using re.VERBOSE
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--------------------
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By now you've probably noticed that regular expressions are a very compact
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@ -29,6 +29,8 @@ Core and Builtins
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Library
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-------
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- Issue #10875: Update Regular Expression HOWTO; patch by 'SilentGhost'.
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- Issue #10827: Changed the rules for 2-digit years. The time.asctime
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function will now format any year when ``time.accept2dyear`` is
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false and will accept years >= 1000 otherwise. The year range
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