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comparison man/lispref/searching.texi @ 1468:0f42689481f0

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[xemacs-hg @ 2003-05-09 14:52:37 by stephent] revert clobber match data <873cjoi38t.fsf@tleepslib.sk.tsukuba.ac.jp>
author stephent
date Fri, 09 May 2003 14:52:43 +0000
parents 1ccc32a20af4
children c3cf7db99b98
comparison
equal deleted inserted replaced
1467:e5da225ea2ca 1468:0f42689481f0
1056 text found during a regular expression search. This means, for example, 1056 text found during a regular expression search. This means, for example,
1057 that you can search for a complex pattern, such as a date in an Rmail 1057 that you can search for a complex pattern, such as a date in an Rmail
1058 message, and then extract parts of the match under control of the 1058 message, and then extract parts of the match under control of the
1059 pattern. 1059 pattern.
1060 1060
1061 Because the match data normally describe the most recent search only, 1061 Because the match data normally describe the most recent successful
1062 you must be careful not to do another search inadvertently between the 1062 search only, you must be careful not to do another search inadvertently
1063 search you wish to refer back to and the use of the match data. If you 1063 between the search you wish to refer back to and the use of the match
1064 can't avoid another intervening search, you must save and restore the 1064 data. If you can't avoid another intervening search, you must save and
1065 match data around it, to prevent it from being overwritten. 1065 restore the match data around it, to prevent it from being overwritten.
1066
1067 To make it possible to write iterative or recursive code that repeatedly
1068 searches, and uses the data from the last successful search when no more
1069 matches can be found, a search or match which fails will preserve the
1070 match data from the last successful search. (You must not depend on
1071 match data being preserved in case the search or match signals an
1072 error.) If for some reason you need to clear the match data, you may
1073 use @code{(store-match-data nil)}.
1066 1074
1067 @menu 1075 @menu
1068 * Simple Match Data:: Accessing single items of match data, 1076 * Simple Match Data:: Accessing single items of match data,
1069 such as where a particular subexpression started. 1077 such as where a particular subexpression started.
1070 * Replacing Match:: Replacing a substring that was matched. 1078 * Replacing Match:: Replacing a substring that was matched.