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Thu Jan 10 17:09:12 2008 UTC (7 years, 3 months ago) by ph10
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Tidies for the 7.5 release.

1 nigel 41 News about PCRE releases
2     ------------------------
4 ph10 298 Release 7.5 10-Jan-08
5 ph10 289 ---------------------
6 ph10 122
7 ph10 289 This is mainly a bug-fix release. However the ability to link pcregrep with
8     libz or libbz2 and the ability to link pcretest with libreadline have been
9     added. Also the --line-offsets and --file-offsets options were added to
10     pcregrep.
13 ph10 260 Release 7.4 21-Sep-07
14 ph10 242 ---------------------
16 ph10 243 The only change of specification is the addition of options to control whether
17 ph10 242 \R matches any Unicode line ending (the default) or just CR, LF, and CRLF.
18 ph10 243 Otherwise, the changes are bug fixes and a refactoring to reduce the number of
19 ph10 261 relocations needed in a shared library. There have also been some documentation
20     updates, in particular, some more information about using CMake to build PCRE
21     has been added to the NON-UNIX-USE file.
22 ph10 242
24 ph10 228 Release 7.3 28-Aug-07
25 ph10 212 ---------------------
27     Most changes are bug fixes. Some that are not:
29     1. There is some support for Perl 5.10's experimental "backtracking control
30     verbs" such as (*PRUNE).
32     2. UTF-8 checking is now as per RFC 3629 instead of RFC 2279; this is more
33     restrictive in the strings it accepts.
35     3. Checking for potential integer overflow has been made more dynamic, and as a
36     consequence there is no longer a hard limit on the size of a subpattern that
37     has a limited repeat count.
38 ph10 227
39     4. When CRLF is a valid line-ending sequence, pcre_exec() and pcre_dfa_exec()
40     no longer advance by two characters instead of one when an unanchored match
41     fails at CRLF if there are explicit CR or LF matches within the pattern.
42 ph10 226 This gets rid of some anomalous effects that previously occurred.
43 ph10 212
44 ph10 227 5. Some PCRE-specific settings for varying the newline options at the start of
45     a pattern have been added.
46 ph10 212
47 ph10 227
48 ph10 184 Release 7.2 19-Jun-07
49 ph10 157 ---------------------
51 ph10 172 WARNING: saved patterns that were compiled by earlier versions of PCRE must be
52 ph10 181 recompiled for use with 7.2 (necessitated by the addition of \K, \h, \H, \v,
53     and \V).
54 ph10 168
55 ph10 159 Correction to the notes for 7.1: the note about shared libraries for Windows is
56     wrong. Previously, three libraries were built, but each could function
57     independently. For example, the pcreposix library also included all the
58     functions from the basic pcre library. The change is that the three libraries
59     are no longer independent. They are like the Unix libraries. To use the
60     pcreposix functions, for example, you need to link with both the pcreposix and
61 ph10 157 the basic pcre library.
63 ph10 166 Some more features from Perl 5.10 have been added:
64 ph10 157
65 ph10 166 (?-n) and (?+n) relative references for recursion and subroutines.
66 ph10 172
67     (?(-n) and (?(+n) relative references as conditions.
68 ph10 182
69 ph10 181 \k{name} and \g{name} are synonyms for \k<name>.
70 ph10 172
71 ph10 168 \K to reset the start of the matched string; for example, (foo)\Kbar
72 ph10 175 matches bar preceded by foo, but only sets bar as the matched string.
73 ph10 182
74     (?| introduces a group where the capturing parentheses in each alternative
75     start from the same number; for example, (?|(abc)|(xyz)) sets capturing
76 ph10 175 parentheses number 1 in both cases.
77 ph10 166
78 ph10 182 \h, \H, \v, \V match horizontal and vertical whitespace, respectively.
79 ph10 166
80 ph10 182
81 ph10 155 Release 7.1 24-Apr-07
82 nigel 93 ---------------------
84 ph10 155 There is only one new feature in this release: a linebreak setting of
85     PCRE_NEWLINE_ANYCRLF. It is a cut-down version of PCRE_NEWLINE_ANY, which
86     recognizes only CRLF, CR, and LF as linebreaks.
87 ph10 122
88 ph10 155 A few bugs are fixed (see ChangeLog for details), but the major change is a
89     complete re-implementation of the build system. This now has full Autotools
90     support and so is now "standard" in some sense. It should help with compiling
91     PCRE in a wide variety of environments.
93 ph10 146 NOTE: when building shared libraries for Windows, three dlls are now built,
94     called libpcre, libpcreposix, and libpcrecpp. Previously, everything was
95     included in a single dll.
97     Another important change is that the dftables auxiliary program is no longer
98 ph10 128 compiled and run at "make" time by default. Instead, a default set of character
99     tables (assuming ASCII coding) is used. If you want to use dftables to generate
100     the character tables as previously, add --enable-rebuild-chartables to the
101     "configure" command. You must do this if you are compiling PCRE to run on a
102     system that uses EBCDIC code.
103 ph10 122
104 ph10 128 There is a discussion about character tables in the README file. The default is
105     not to use dftables so that that there is no problem when cross-compiling.
108 ph10 122 Release 7.0 19-Dec-06
109     ---------------------
111 nigel 93 This release has a new major number because there have been some internal
112     upheavals to facilitate the addition of new optimizations and other facilities,
113     and to make subsequent maintenance and extension easier. Compilation is likely
114     to be a bit slower, but there should be no major effect on runtime performance.
115     Previously compiled patterns are NOT upwards compatible with this release. If
116     you have saved compiled patterns from a previous release, you will have to
117     re-compile them. Important changes that are visible to users are:
119     1. The Unicode property tables have been updated to Unicode 5.0.0, which adds
120     some more scripts.
122     2. The option PCRE_NEWLINE_ANY causes PCRE to recognize any Unicode newline
123     sequence as a newline.
125     3. The \R escape matches a single Unicode newline sequence as a single unit.
127     4. New features that will appear in Perl 5.10 are now in PCRE. These include
128     alternative Perl syntax for named parentheses, and Perl syntax for
129     recursion.
131     5. The C++ wrapper interface has been extended by the addition of a
132     QuoteMeta function and the ability to allow copy construction and
133     assignment.
135     For a complete list of changes, see the ChangeLog file.
138 nigel 91 Release 6.7 04-Jul-06
139     ---------------------
141     The main additions to this release are the ability to use the same name for
142     multiple sets of parentheses, and support for CRLF line endings in both the
143     library and pcregrep (and in pcretest for testing).
145     Thanks to Ian Taylor, the stack usage for many kinds of pattern has been
146     significantly reduced for certain subject strings.
149 nigel 87 Release 6.5 01-Feb-06
150     ---------------------
152     Important changes in this release:
154     1. A number of new features have been added to pcregrep.
156     2. The Unicode property tables have been updated to Unicode 4.1.0, and the
157     supported properties have been extended with script names such as "Arabic",
158     and the derived properties "Any" and "L&". This has necessitated a change to
159     the interal format of compiled patterns. Any saved compiled patterns that
160     use \p or \P must be recompiled.
162     3. The specification of recursion in patterns has been changed so that all
163     recursive subpatterns are automatically treated as atomic groups. Thus, for
164     example, (?R) is treated as if it were (?>(?R)). This is necessary because
165     otherwise there are situations where recursion does not work.
167     See the ChangeLog for a complete list of changes, which include a number of bug
168     fixes and tidies.
171 nigel 77 Release 6.0 07-Jun-05
172     ---------------------
174     The release number has been increased to 6.0 because of the addition of several
175     major new pieces of functionality.
177     A new function, pcre_dfa_exec(), which implements pattern matching using a DFA
178     algorithm, has been added. This has a number of advantages for certain cases,
179     though it does run more slowly, and lacks the ability to capture substrings. On
180     the other hand, it does find all matches, not just the first, and it works
181     better for partial matching. The pcrematching man page discusses the
182     differences.
184     The pcretest program has been enhanced so that it can make use of the new
185     pcre_dfa_exec() matching function and the extra features it provides.
187     The distribution now includes a C++ wrapper library. This is built
188     automatically if a C++ compiler is found. The pcrecpp man page discusses this
189     interface.
191     The code itself has been re-organized into many more files, one for each
192     function, so it no longer requires everything to be linked in when static
193     linkage is used. As a consequence, some internal functions have had to have
194     their names exposed. These functions all have names starting with _pcre_. They
195     are undocumented, and are not intended for use by outside callers.
197     The pcregrep program has been enhanced with new functionality such as
198     multiline-matching and options for output more matching context. See the
199     ChangeLog for a complete list of changes to the library and the utility
200     programs.
203 nigel 75 Release 5.0 13-Sep-04
204     ---------------------
206     The licence under which PCRE is released has been changed to the more
207     conventional "BSD" licence.
209     In the code, some bugs have been fixed, and there are also some major changes
210     in this release (which is why I've increased the number to 5.0). Some changes
211     are internal rearrangements, and some provide a number of new facilities. The
212     new features are:
214     1. There's an "automatic callout" feature that inserts callouts before every
215     item in the regex, and there's a new callout field that gives the position
216     in the pattern - useful for debugging and tracing.
218     2. The extra_data structure can now be used to pass in a set of character
219     tables at exec time. This is useful if compiled regex are saved and re-used
220     at a later time when the tables may not be at the same address. If the
221     default internal tables are used, the pointer saved with the compiled
222     pattern is now set to NULL, which means that you don't need to do anything
223     special unless you are using custom tables.
225     3. It is possible, with some restrictions on the content of the regex, to
226     request "partial" matching. A special return code is given if all of the
227     subject string matched part of the regex. This could be useful for testing
228     an input field as it is being typed.
230     4. There is now some optional support for Unicode character properties, which
231     means that the patterns items such as \p{Lu} and \X can now be used. Only
232     the general category properties are supported. If PCRE is compiled with this
233     support, an additional 90K data structure is include, which increases the
234     size of the library dramatically.
236     5. There is support for saving compiled patterns and re-using them later.
238     6. There is support for running regular expressions that were compiled on a
239     different host with the opposite endianness.
241     7. The pcretest program has been extended to accommodate the new features.
243     The main internal rearrangement is that sequences of literal characters are no
244     longer handled as strings. Instead, each character is handled on its own. This
245     makes some UTF-8 handling easier, and makes the support of partial matching
246     possible. Compiled patterns containing long literal strings will be larger as a
247     result of this change; I hope that performance will not be much affected.
250 nigel 73 Release 4.5 01-Dec-03
251     ---------------------
253     Again mainly a bug-fix and tidying release, with only a couple of new features:
255     1. It's possible now to compile PCRE so that it does not use recursive
256     function calls when matching. Instead it gets memory from the heap. This slows
257     things down, but may be necessary on systems with limited stacks.
259     2. UTF-8 string checking has been tightened to reject overlong sequences and to
260     check that a starting offset points to the start of a character. Failure of the
261     latter returns a new error code: PCRE_ERROR_BADUTF8_OFFSET.
263     3. PCRE can now be compiled for systems that use EBCDIC code.
266 nigel 71 Release 4.4 21-Aug-03
267     ---------------------
269     This is mainly a bug-fix and tidying release. The only new feature is that PCRE
270     checks UTF-8 strings for validity by default. There is an option to suppress
271     this, just in case anybody wants that teeny extra bit of performance.
274     Releases 4.1 - 4.3
275     ------------------
277     Sorry, I forgot about updating the NEWS file for these releases. Please take a
278     look at ChangeLog.
281 nigel 63 Release 4.0 17-Feb-03
282     ---------------------
284     There have been a lot of changes for the 4.0 release, adding additional
285     functionality and mending bugs. Below is a list of the highlights of the new
286     functionality. For full details of these features, please consult the
287     documentation. For a complete list of changes, see the ChangeLog file.
289     1. Support for Perl's \Q...\E escapes.
291     2. "Possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's Java
292     package. They provide some syntactic sugar for simple cases of "atomic
293     grouping".
295     3. Support for the \G assertion. It is true when the current matching position
296     is at the start point of the match.
298     4. A new feature that provides some of the functionality that Perl provides
299     with (?{...}). The facility is termed a "callout". The way it is done in PCRE
300     is for the caller to provide an optional function, by setting pcre_callout to
301     its entry point. To get the function called, the regex must include (?C) at
302     appropriate points.
304     5. Support for recursive calls to individual subpatterns. This makes it really
305     easy to get totally confused.
307     6. Support for named subpatterns. The Python syntax (?P<name>...) is used to
308     name a group.
310     7. Several extensions to UTF-8 support; it is now fairly complete. There is an
311     option for pcregrep to make it operate in UTF-8 mode.
313     8. The single man page has been split into a number of separate man pages.
314     These also give rise to individual HTML pages which are put in a separate
315     directory. There is an index.html page that lists them all. Some hyperlinking
316     between the pages has been installed.
319 nigel 53 Release 3.5 15-Aug-01
320     ---------------------
322     1. The configuring system has been upgraded to use later versions of autoconf
323     and libtool. By default it builds both a shared and a static library if the OS
324     supports it. You can use --disable-shared or --disable-static on the configure
325     command if you want only one of them.
327     2. The pcretest utility is now installed along with pcregrep because it is
328     useful for users (to test regexs) and by doing this, it automatically gets
329     relinked by libtool. The documentation has been turned into a man page, so
330     there are now .1, .txt, and .html versions in /doc.
332     3. Upgrades to pcregrep:
333     (i) Added long-form option names like gnu grep.
334     (ii) Added --help to list all options with an explanatory phrase.
335     (iii) Added -r, --recursive to recurse into sub-directories.
336     (iv) Added -f, --file to read patterns from a file.
338     4. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
339     script, to force use of CR or LF instead of \n in the source. On non-Unix
340     systems, the value can be set in config.h.
342     5. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
343     absolute limit. Changed the text of the error message to make this clear, and
344     likewise updated the man page.
346     6. The limit of 99 on the number of capturing subpatterns has been removed.
347     The new limit is 65535, which I hope will not be a "real" limit.
350 nigel 49 Release 3.3 01-Aug-00
351     ---------------------
353     There is some support for UTF-8 character strings. This is incomplete and
354     experimental. The documentation describes what is and what is not implemented.
355     Otherwise, this is just a bug-fixing release.
358 nigel 43 Release 3.0 01-Feb-00
359     ---------------------
360 nigel 41
361 nigel 43 1. A "configure" script is now used to configure PCRE for Unix systems. It
362     builds a Makefile, a config.h file, and the pcre-config script.
364     2. PCRE is built as a shared library by default.
366     3. There is support for POSIX classes such as [:alpha:].
368     5. There is an experimental recursion feature.
370 nigel 41 ----------------------------------------------------------------------------
373     Please note that there has been a change in the API such that a larger
374     ovector is required at matching time, to provide some additional workspace.
375     The new man page has details. This change was necessary in order to support
376     some of the new functionality in Perl 5.005.
380     Another (I hope this is the last!) change has been made to the API for the
381     pcre_compile() function. An additional argument has been added to make it
382     possible to pass over a pointer to character tables built in the current
383     locale by pcre_maketables(). To use the default tables, this new arguement
384     should be passed as NULL.
388     Yet another (and again I hope this really is the last) change has been made
389     to the API for the pcre_exec() function. An additional argument has been
390     added to make it possible to start the match other than at the start of the
391     subject string. This is important if there are lookbehinds. The new man
392     page has the details, but you just want to convert existing programs, all
393     you need to do is to stick in a new fifth argument to pcre_exec(), with a
394     value of zero. For example, change
396     pcre_exec(pattern, extra, subject, length, options, ovec, ovecsize)
397     to
398     pcre_exec(pattern, extra, subject, length, 0, options, ovec, ovecsize)
400     ****


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