Revision: 756
http://www.exim.org/viewvc/pcre2?view=rev&revision=756
Author: ph10
Date: 2017-04-17 16:39:09 +0100 (Mon, 17 Apr 2017)
Log Message:
-----------
Documentation update.
Modified Paths:
--------------
code/trunk/doc/html/pcre2compat.html
code/trunk/doc/pcre2.txt
code/trunk/doc/pcre2compat.3
Modified: code/trunk/doc/html/pcre2compat.html
===================================================================
--- code/trunk/doc/html/pcre2compat.html 2017-04-17 15:24:41 UTC (rev 755)
+++ code/trunk/doc/html/pcre2compat.html 2017-04-17 15:39:09 UTC (rev 756)
@@ -18,7 +18,7 @@
<P>
This document describes the differences in the ways that PCRE2 and Perl handle
regular expressions. The differences described here are with respect to Perl
-versions 5.24, but as both Perl and PCRE2 are continually changing, the
+versions 5.26, but as both Perl and PCRE2 are continually changing, the
information may sometimes be out of date.
</P>
<P>
@@ -148,7 +148,7 @@
17. PCRE2 provides some extensions to the Perl regular expression facilities.
Perl 5.10 includes new features that are not in earlier versions of Perl, some
of which (such as named parentheses) were in PCRE2 for some time before. This
-list is with respect to Perl 5.24:
+list is with respect to Perl 5.26:
<br>
<br>
(a) Although lookbehind assertions in PCRE2 must match fixed length strings,
@@ -178,8 +178,8 @@
only at the first matching position in the subject string.
<br>
<br>
-(g) The PCRE2_NOTBOL, PCRE2_NOTEOL, PCRE2_NOTEMPTY, PCRE2_NOTEMPTY_ATSTART, and
-PCRE2_NO_AUTO_CAPTURE options have no Perl equivalents.
+(g) The PCRE2_NOTBOL, PCRE2_NOTEOL, PCRE2_NOTEMPTY and PCRE2_NOTEMPTY_ATSTART
+options have no Perl equivalents.
<br>
<br>
(h) The \R escape sequence can be restricted to match only CR, LF, or CRLF
@@ -186,7 +186,8 @@
by the PCRE2_BSR_ANYCRLF option.
<br>
<br>
-(i) The callout facility is PCRE2-specific.
+(i) The callout facility is PCRE2-specific. Perl supports codeblocks and
+variable interpolation, but not general hooks on every match.
<br>
<br>
(j) The partial matching facility is PCRE2-specific.
@@ -196,8 +197,25 @@
different way and is not Perl-compatible.
<br>
<br>
-(l) PCRE2 recognizes some special sequences such as (*CR) at the start of
-a pattern that set overall options that cannot be changed within the pattern.
+(l) PCRE2 recognizes some special sequences such as (*CR) or (*NO_JIT) at
+the start of a pattern that set overall options that cannot be changed within
+the pattern.
+<br>
+<br>
+18. The following new Perl 5.26 constructs are not yet supported in PCRE2:
+<br>
+<br>
+(a) The Perl /a modifier restricts /d numbers to pure ascii, the new /aa
+modifier restricts /i case-insensitive matching to pure ascii also, ignoring
+unicode rules. This separation cannot be represented with PCRE2_UTF.
+<br>
+<br>
+19. Perl has different limits than PCRE2. See the
+<a href="pcre2limit.html"><b>pcre2limit</b></a>
+documentation for details. Perl went with 5.10 from recursion to iteration
+keeping the intermediate matches on the heap, which is ~10% slower but does not
+fall into any stack-overflow limit. PCRE2 made a similar change at release
+10.30, and also has many build-time and run-time customizable limits.
</P>
<br><b>
AUTHOR
@@ -214,7 +232,7 @@
REVISION
</b><br>
<P>
-Last updated: 03 April 2017
+Last updated: 17 April 2017
<br>
Copyright © 1997-2017 University of Cambridge.
<br>
Modified: code/trunk/doc/pcre2.txt
===================================================================
--- code/trunk/doc/pcre2.txt 2017-04-17 15:24:41 UTC (rev 755)
+++ code/trunk/doc/pcre2.txt 2017-04-17 15:39:09 UTC (rev 756)
@@ -4203,7 +4203,7 @@
This document describes the differences in the ways that PCRE2 and Perl
handle regular expressions. The differences described here are with
- respect to Perl versions 5.24, but as both Perl and PCRE2 are continu-
+ respect to Perl versions 5.26, but as both Perl and PCRE2 are continu-
ally changing, the information may sometimes be out of date.
1. PCRE2 has only a subset of Perl's Unicode support. Details of what
@@ -4320,7 +4320,7 @@
17. PCRE2 provides some extensions to the Perl regular expression
facilities. Perl 5.10 includes new features that are not in earlier
versions of Perl, some of which (such as named parentheses) were in
- PCRE2 for some time before. This list is with respect to Perl 5.24:
+ PCRE2 for some time before. This list is with respect to Perl 5.26:
(a) Although lookbehind assertions in PCRE2 must match fixed length
strings, each alternative branch of a lookbehind assertion can match a
@@ -4345,14 +4345,14 @@
(f) PCRE2_ANCHORED can be used at matching time to force a pattern to
be tried only at the first matching position in the subject string.
- (g) The PCRE2_NOTBOL, PCRE2_NOTEOL, PCRE2_NOTEMPTY,
- PCRE2_NOTEMPTY_ATSTART, and PCRE2_NO_AUTO_CAPTURE options have no Perl
- equivalents.
+ (g) The PCRE2_NOTBOL, PCRE2_NOTEOL, PCRE2_NOTEMPTY and
+ PCRE2_NOTEMPTY_ATSTART options have no Perl equivalents.
- (h) The \R escape sequence can be restricted to match only CR, LF, or
+ (h) The \R escape sequence can be restricted to match only CR, LF, or
CRLF by the PCRE2_BSR_ANYCRLF option.
- (i) The callout facility is PCRE2-specific.
+ (i) The callout facility is PCRE2-specific. Perl supports codeblocks
+ and variable interpolation, but not general hooks on every match.
(j) The partial matching facility is PCRE2-specific.
@@ -4359,11 +4359,26 @@
(k) The alternative matching function (pcre2_dfa_match() matches in a
different way and is not Perl-compatible.
- (l) PCRE2 recognizes some special sequences such as (*CR) at the start
- of a pattern that set overall options that cannot be changed within the
- pattern.
+ (l) PCRE2 recognizes some special sequences such as (*CR) or (*NO_JIT)
+ at the start of a pattern that set overall options that cannot be
+ changed within the pattern.
+ 18. The following new Perl 5.26 constructs are not yet supported in
+ PCRE2:
+ (a) The Perl /a modifier restricts /d numbers to pure ascii, the new
+ /aa modifier restricts /i case-insensitive matching to pure ascii also,
+ ignoring unicode rules. This separation cannot be represented with
+ PCRE2_UTF.
+
+ 19. Perl has different limits than PCRE2. See the pcre2limit documenta-
+ tion for details. Perl went with 5.10 from recursion to iteration keep-
+ ing the intermediate matches on the heap, which is ~10% slower but does
+ not fall into any stack-overflow limit. PCRE2 made a similar change at
+ release 10.30, and also has many build-time and run-time customizable
+ limits.
+
+
AUTHOR
Philip Hazel
@@ -4373,7 +4388,7 @@
REVISION
- Last updated: 03 April 2017
+ Last updated: 17 April 2017
Copyright (c) 1997-2017 University of Cambridge.
------------------------------------------------------------------------------
Modified: code/trunk/doc/pcre2compat.3
===================================================================
--- code/trunk/doc/pcre2compat.3 2017-04-17 15:24:41 UTC (rev 755)
+++ code/trunk/doc/pcre2compat.3 2017-04-17 15:39:09 UTC (rev 756)
@@ -1,4 +1,4 @@
-.TH PCRE2COMPAT 3 "03 April 2017" "PCRE2 10.30"
+.TH PCRE2COMPAT 3 "17 April 2017" "PCRE2 10.30"
.SH NAME
PCRE2 - Perl-compatible regular expressions (revised API)
.SH "DIFFERENCES BETWEEN PCRE2 AND PERL"
@@ -6,7 +6,7 @@
.sp
This document describes the differences in the ways that PCRE2 and Perl handle
regular expressions. The differences described here are with respect to Perl
-versions 5.24, but as both Perl and PCRE2 are continually changing, the
+versions 5.26, but as both Perl and PCRE2 are continually changing, the
information may sometimes be out of date.
.P
1. PCRE2 has only a subset of Perl's Unicode support. Details of what it does
@@ -125,7 +125,7 @@
17. PCRE2 provides some extensions to the Perl regular expression facilities.
Perl 5.10 includes new features that are not in earlier versions of Perl, some
of which (such as named parentheses) were in PCRE2 for some time before. This
-list is with respect to Perl 5.24:
+list is with respect to Perl 5.26:
.sp
(a) Although lookbehind assertions in PCRE2 must match fixed length strings,
each alternative branch of a lookbehind assertion can match a different length
@@ -148,13 +148,14 @@
(f) PCRE2_ANCHORED can be used at matching time to force a pattern to be tried
only at the first matching position in the subject string.
.sp
-(g) The PCRE2_NOTBOL, PCRE2_NOTEOL, PCRE2_NOTEMPTY, PCRE2_NOTEMPTY_ATSTART, and
-PCRE2_NO_AUTO_CAPTURE options have no Perl equivalents.
+(g) The PCRE2_NOTBOL, PCRE2_NOTEOL, PCRE2_NOTEMPTY and PCRE2_NOTEMPTY_ATSTART
+options have no Perl equivalents.
.sp
(h) The \eR escape sequence can be restricted to match only CR, LF, or CRLF
by the PCRE2_BSR_ANYCRLF option.
.sp
-(i) The callout facility is PCRE2-specific.
+(i) The callout facility is PCRE2-specific. Perl supports codeblocks and
+variable interpolation, but not general hooks on every match.
.sp
(j) The partial matching facility is PCRE2-specific.
.sp
@@ -161,8 +162,24 @@
(k) The alternative matching function (\fBpcre2_dfa_match()\fP matches in a
different way and is not Perl-compatible.
.sp
-(l) PCRE2 recognizes some special sequences such as (*CR) at the start of
-a pattern that set overall options that cannot be changed within the pattern.
+(l) PCRE2 recognizes some special sequences such as (*CR) or (*NO_JIT) at
+the start of a pattern that set overall options that cannot be changed within
+the pattern.
+.sp
+18. The following new Perl 5.26 constructs are not yet supported in PCRE2:
+.sp
+(a) The Perl /a modifier restricts /d numbers to pure ascii, the new /aa
+modifier restricts /i case-insensitive matching to pure ascii also, ignoring
+unicode rules. This separation cannot be represented with PCRE2_UTF.
+.sp
+19. Perl has different limits than PCRE2. See the
+.\" HREF
+\fBpcre2limit\fP
+.\"
+documentation for details. Perl went with 5.10 from recursion to iteration
+keeping the intermediate matches on the heap, which is ~10% slower but does not
+fall into any stack-overflow limit. PCRE2 made a similar change at release
+10.30, and also has many build-time and run-time customizable limits.
.
.
.SH AUTHOR
@@ -179,6 +196,6 @@
.rs
.sp
.nf
-Last updated: 03 April 2017
+Last updated: 17 April 2017
Copyright (c) 1997-2017 University of Cambridge.
.fi
