#14155: remove duplication about search vs match in re doc.
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@ -423,31 +423,6 @@ a group reference. As for string literals, octal escapes are always at most
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three digits in length.
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.. _matching-searching:
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Matching vs. Searching
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----------------------
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.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
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Python offers two different primitive operations based on regular expressions:
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**match** checks for a match only at the beginning of the string, while
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**search** checks for a match anywhere in the string (this is what Perl does
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by default).
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Note that match may differ from search even when using a regular expression
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beginning with ``'^'``: ``'^'`` matches only at the start of the string, or in
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:const:`MULTILINE` mode also immediately following a newline. The "match"
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operation succeeds only if the pattern matches at the start of the string
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regardless of mode, or at the starting position given by the optional *pos*
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argument regardless of whether a newline precedes it.
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>>> re.match("c", "abcdef") # No match
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>>> re.search("c", "abcdef") # Match
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<_sre.SRE_Match object at ...>
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.. _contents-of-module-re:
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Module Contents
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@ -581,10 +556,11 @@ form.
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<match-objects>`. Return ``None`` if the string does not match the pattern;
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note that this is different from a zero-length match.
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.. note::
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Note that even in :const:`MULTILINE` mode, :func:`re.match` will only match
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at the beginning of the string and not at the beginning of each line.
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If you want to locate a match anywhere in *string*, use :func:`search`
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instead.
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If you want to locate a match anywhere in *string*, use :func:`search`
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instead (see also :ref:`search-vs-match`).
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.. function:: split(pattern, string, maxsplit=0, flags=0)
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@ -768,16 +744,14 @@ attributes:
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The optional *pos* and *endpos* parameters have the same meaning as for the
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:meth:`~regex.search` method.
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.. note::
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If you want to locate a match anywhere in *string*, use
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:meth:`~regex.search` instead.
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>>> pattern = re.compile("o")
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>>> pattern.match("dog") # No match as "o" is not at the start of "dog".
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>>> pattern.match("dog", 1) # Match as "o" is the 2nd character of "dog".
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<_sre.SRE_Match object at ...>
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If you want to locate a match anywhere in *string*, use
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:meth:`~regex.search` instead (see also :ref:`search-vs-match`).
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.. method:: regex.split(string, maxsplit=0)
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@ -1139,37 +1113,39 @@ the above regular expression can avoid recursion by being recast as ``Begin
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[a-zA-Z0-9_ ]*?end``. As a further benefit, such regular expressions will run
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faster than their recursive equivalents.
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.. _search-vs-match:
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search() vs. match()
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^^^^^^^^^^^^^^^^^^^^
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In a nutshell, :func:`match` only attempts to match a pattern at the beginning
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of a string where :func:`search` will match a pattern anywhere in a string.
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For example:
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.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
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>>> re.match("o", "dog") # No match as "o" is not the first letter of "dog".
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>>> re.search("o", "dog") # Match as search() looks everywhere in the string.
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Python offers two different primitive operations based on regular expressions:
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:func:`re.match` checks for a match only at the beginning of the string, while
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:func:`re.search` checks for a match anywhere in the string (this is what Perl
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does by default).
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For example::
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>>> re.match("c", "abcdef") # No match
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>>> re.search("c", "abcdef") # Match
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<_sre.SRE_Match object at ...>
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.. note::
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Regular expressions beginning with ``'^'`` can be used with :func:`search` to
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restrict the match at the beginning of the string::
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The following applies only to regular expression objects like those created
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with ``re.compile("pattern")``, not the primitives ``re.match(pattern,
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string)`` or ``re.search(pattern, string)``.
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:func:`match` has an optional second parameter that gives an index in the string
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where the search is to start::
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>>> pattern = re.compile("o")
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>>> pattern.match("dog") # No match as "o" is not at the start of "dog."
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# Equivalent to the above expression as 0 is the default starting index:
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>>> pattern.match("dog", 0)
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# Match as "o" is the 2nd character of "dog" (index 0 is the first):
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>>> pattern.match("dog", 1)
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>>> re.match("c", "abcdef") # No match
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>>> re.search("^c", "abcdef") # No match
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>>> re.search("^a", "abcdef") # Match
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<_sre.SRE_Match object at ...>
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Note however that in :const:`MULTILINE` mode :func:`match` only matches at the
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beginning of the string, whereas using :func:`search` with a regular expression
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beginning with ``'^'`` will match at the beginning of each line.
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>>> re.match('X', 'A\nB\nX', re.MULTILINE) # No match
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>>> re.search('^X', 'A\nB\nX', re.MULTILINE) # Match
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<_sre.SRE_Match object at ...>
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>>> pattern.match("dog", 2) # No match as "o" is not the 3rd character of "dog."
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Making a Phonebook
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