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Update bundled PCRE2-library to version 10.23

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Some manual changes done to the library were lost with this update.
They will be added in the next commit.
This commit is contained in:
Esa Korhonen
2017-05-29 15:31:42 +03:00
parent 7231563937
commit 36af74cb25
218 changed files with 49218 additions and 26130 deletions
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42
pcre2/doc/html/pcre2callout.html
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@ -57,11 +57,20 @@ two callout points:
</pre>
If the PCRE2_AUTO_CALLOUT option bit is set when a pattern is compiled, PCRE2
automatically inserts callouts, all with number 255, before each item in the
pattern. For example, if PCRE2_AUTO_CALLOUT is used with the pattern
pattern except for immediately before or after a callout item in the pattern.
For example, if PCRE2_AUTO_CALLOUT is used with the pattern
<pre>
A(?C3)B
</pre>
it is processed as if it were
<pre>
(?C255)A(?C3)B(?C255)
</pre>
Here is a more complicated example:
<pre>
A(\d{2}|--)
</pre>
it is processed as if it were
With PCRE2_AUTO_CALLOUT, this pattern is processed as if it were
<br>
<br>
(?C255)A(?C255)((?C255)\d{2}(?C255)|(?C255)-(?C255)-(?C255))(?C255)
@ -107,10 +116,10 @@ with PCRE2_ANCHORED and PCRE2_AUTO_CALLOUT and then applied to the string
No match
</pre>
This indicates that when matching [bc] fails, there is no backtracking into a+
and therefore the callouts that would be taken for the backtracks do not occur.
You can disable the auto-possessify feature by passing PCRE2_NO_AUTO_POSSESS to
<b>pcre2_compile()</b>, or starting the pattern with (*NO_AUTO_POSSESS). In this
case, the output changes to this:
(because it is being treated as a++) and therefore the callouts that would be
taken for the backtracks do not occur. You can disable the auto-possessify
feature by passing PCRE2_NO_AUTO_POSSESS to <b>pcre2_compile()</b>, or starting
the pattern with (*NO_AUTO_POSSESS). In this case, the output changes to this:
<pre>
---&#62;aaaa
+0 ^ a+
@ -235,8 +244,8 @@ Fields for numerical callouts
<P>
For a numerical callout, <i>callout_string</i> is NULL, and <i>callout_number</i>
contains the number of the callout, in the range 0-255. This is the number
that follows (?C for manual callouts; it is 255 for automatically generated
callouts.
that follows (?C for callouts that part of the pattern; it is 255 for
automatically generated callouts.
</P>
<br><b>
Fields for string callouts
@ -310,10 +319,15 @@ the next item to be matched.
</P>
<P>
The <i>next_item_length</i> field contains the length of the next item to be
matched in the pattern string. When the callout immediately precedes an
alternation bar, a closing parenthesis, or the end of the pattern, the length
is zero. When the callout precedes an opening parenthesis, the length is that
of the entire subpattern.
processed in the pattern string. When the callout is at the end of the pattern,
the length is zero. When the callout precedes an opening parenthesis, the
length includes meta characters that follow the parenthesis. For example, in a
callout before an assertion such as (?=ab) the length is 3. For an an
alternation bar or a closing parenthesis, the length is one, unless a closing
parenthesis is followed by a quantifier, in which case its length is included.
(This changed in release 10.23. In earlier releases, before an opening
parenthesis the length was that of the entire subpattern, and before an
alternation bar or a closing parenthesis the length was zero.)
</P>
<P>
The <i>pattern_position</i> and <i>next_item_length</i> fields are intended to
@ -399,9 +413,9 @@ Cambridge, England.
</P>
<br><a name="SEC8" href="#TOC1">REVISION</a><br>
<P>
Last updated: 23 March 2015
Last updated: 29 September 2016
<br>
Copyright &copy; 1997-2015 University of Cambridge.
Copyright &copy; 1997-2016 University of Cambridge.
<br>
<p>
Return to the <a href="index.html">PCRE2 index page</a>.