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diff --git a/srclib/pcre/doc/html/pcrepartial.html b/srclib/pcre/doc/html/pcrepartial.html deleted file mode 100644 index c4dd88613b..0000000000 --- a/srclib/pcre/doc/html/pcrepartial.html +++ /dev/null @@ -1,111 +0,0 @@ -<html> -<head> -<title>pcrepartial specification</title> -</head> -<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB"> -<h1>pcrepartial man page</h1> -<p> -Return to the <a href="index.html">PCRE index page</a>. -</p> -<p> -This page is part of the PCRE HTML documentation. It was generated automatically -from the original man page. If there is any nonsense in it, please consult the -man page, in case the conversion went wrong. -<br> -<ul> -<li><a name="TOC1" href="#SEC1">PARTIAL MATCHING IN PCRE</a> -<li><a name="TOC2" href="#SEC2">RESTRICTED PATTERNS FOR PCRE_PARTIAL</a> -<li><a name="TOC3" href="#SEC3">EXAMPLE OF PARTIAL MATCHING USING PCRETEST</a> -</ul> -<br><a name="SEC1" href="#TOC1">PARTIAL MATCHING IN PCRE</a><br> -<P> -In normal use of PCRE, if the subject string that is passed to -<b>pcre_exec()</b> matches as far as it goes, but is too short to match the -entire pattern, PCRE_ERROR_NOMATCH is returned. There are circumstances where -it might be helpful to distinguish this case from other cases in which there is -no match. -</P> -<P> -Consider, for example, an application where a human is required to type in data -for a field with specific formatting requirements. An example might be a date -in the form <i>ddmmmyy</i>, defined by this pattern: -<pre> - ^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$ -</pre> -If the application sees the user's keystrokes one by one, and can check that -what has been typed so far is potentially valid, it is able to raise an error -as soon as a mistake is made, possibly beeping and not reflecting the -character that has been typed. This immediate feedback is likely to be a better -user interface than a check that is delayed until the entire string has been -entered. -</P> -<P> -PCRE supports the concept of partial matching by means of the PCRE_PARTIAL -option, which can be set when calling <b>pcre_exec()</b>. When this is done, the -return code PCRE_ERROR_NOMATCH is converted into PCRE_ERROR_PARTIAL if at any -time during the matching process the entire subject string matched part of the -pattern. No captured data is set when this occurs. -</P> -<P> -Using PCRE_PARTIAL disables one of PCRE's optimizations. PCRE remembers the -last literal byte in a pattern, and abandons matching immediately if such a -byte is not present in the subject string. This optimization cannot be used -for a subject string that might match only partially. -</P> -<br><a name="SEC2" href="#TOC1">RESTRICTED PATTERNS FOR PCRE_PARTIAL</a><br> -<P> -Because of the way certain internal optimizations are implemented in PCRE, the -PCRE_PARTIAL option cannot be used with all patterns. Repeated single -characters such as -<pre> - a{2,4} -</pre> -and repeated single metasequences such as -<pre> - \d+ -</pre> -are not permitted if the maximum number of occurrences is greater than one. -Optional items such as \d? (where the maximum is one) are permitted. -Quantifiers with any values are permitted after parentheses, so the invalid -examples above can be coded thus: -<pre> - (a){2,4} - (\d)+ -</pre> -These constructions run more slowly, but for the kinds of application that are -envisaged for this facility, this is not felt to be a major restriction. -</P> -<P> -If PCRE_PARTIAL is set for a pattern that does not conform to the restrictions, -<b>pcre_exec()</b> returns the error code PCRE_ERROR_BADPARTIAL (-13). -</P> -<br><a name="SEC3" href="#TOC1">EXAMPLE OF PARTIAL MATCHING USING PCRETEST</a><br> -<P> -If the escape sequence \P is present in a <b>pcretest</b> data line, the -PCRE_PARTIAL flag is used for the match. Here is a run of <b>pcretest</b> that -uses the date example quoted above: -<pre> - re> /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/ - data> 25jun04\P - 0: 25jun04 - 1: jun - data> 25dec3\P - Partial match - data> 3ju\P - Partial match - data> 3juj\P - No match - data> j\P - No match -</pre> -The first data string is matched completely, so <b>pcretest</b> shows the -matched substrings. The remaining four strings do not match the complete -pattern, but the first two are partial matches. -</P> -<P> -Last updated: 08 September 2004 -<br> -Copyright © 1997-2004 University of Cambridge. -<p> -Return to the <a href="index.html">PCRE index page</a>. -</p> |