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55 | <H2><A NAME="SECTION006220000000000000000"></A><A NAME="matching-searching"></A> | |
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57 | 4.2.2 Matching vs Searching | |
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59 | ||
60 | <P> | |
61 | Python offers two different primitive operations based on regular | |
62 | expressions: match and search. If you are accustomed to Perl's | |
63 | semantics, the search operation is what you're looking for. See the | |
64 | <tt class="function">search()</tt> function and corresponding method of compiled | |
65 | regular expression objects. | |
66 | ||
67 | <P> | |
68 | Note that match may differ from search using a regular expression | |
69 | beginning with "<tt class="character">^</tt>": | |
70 | "<tt class="character">^</tt>" matches only at the | |
71 | start of the string, or in <tt class="constant">MULTILINE</tt> mode also immediately | |
72 | following a newline. The ``match'' operation succeeds only if the | |
73 | pattern matches at the start of the string regardless of mode, or at | |
74 | the starting position given by the optional <var>pos</var> argument | |
75 | regardless of whether a newline precedes it. | |
76 | ||
77 | <P> | |
78 | <div class="verbatim"><pre> | |
79 | re.compile("a").match("ba", 1) # succeeds | |
80 | re.compile("^a").search("ba", 1) # fails; 'a' not at start | |
81 | re.compile("^a").search("\na", 1) # fails; 'a' not at start | |
82 | re.compile("^a", re.M).search("\na", 1) # succeeds | |
83 | re.compile("^a", re.M).search("ba", 1) # fails; no preceding \n | |
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