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Revision 184 - (show annotations) (download)
Tue Jun 19 13:26:46 2007 UTC (7 years, 3 months ago) by ph10
File size: 14998 byte(s)
Fix non-UTF-8 mode Unicode properties bug; prepare for 7.2 release.

1 News about PCRE releases
2 ------------------------
3
4
5 Release 7.2 19-Jun-07
6 ---------------------
7
8 WARNING: saved patterns that were compiled by earlier versions of PCRE must be
9 recompiled for use with 7.2 (necessitated by the addition of \K, \h, \H, \v,
10 and \V).
11
12 Correction to the notes for 7.1: the note about shared libraries for Windows is
13 wrong. Previously, three libraries were built, but each could function
14 independently. For example, the pcreposix library also included all the
15 functions from the basic pcre library. The change is that the three libraries
16 are no longer independent. They are like the Unix libraries. To use the
17 pcreposix functions, for example, you need to link with both the pcreposix and
18 the basic pcre library.
19
20 Some more features from Perl 5.10 have been added:
21
22 (?-n) and (?+n) relative references for recursion and subroutines.
23
24 (?(-n) and (?(+n) relative references as conditions.
25
26 \k{name} and \g{name} are synonyms for \k<name>.
27
28 \K to reset the start of the matched string; for example, (foo)\Kbar
29 matches bar preceded by foo, but only sets bar as the matched string.
30
31 (?| introduces a group where the capturing parentheses in each alternative
32 start from the same number; for example, (?|(abc)|(xyz)) sets capturing
33 parentheses number 1 in both cases.
34
35 \h, \H, \v, \V match horizontal and vertical whitespace, respectively.
36
37
38 Release 7.1 24-Apr-07
39 ---------------------
40
41 There is only one new feature in this release: a linebreak setting of
42 PCRE_NEWLINE_ANYCRLF. It is a cut-down version of PCRE_NEWLINE_ANY, which
43 recognizes only CRLF, CR, and LF as linebreaks.
44
45 A few bugs are fixed (see ChangeLog for details), but the major change is a
46 complete re-implementation of the build system. This now has full Autotools
47 support and so is now "standard" in some sense. It should help with compiling
48 PCRE in a wide variety of environments.
49
50 NOTE: when building shared libraries for Windows, three dlls are now built,
51 called libpcre, libpcreposix, and libpcrecpp. Previously, everything was
52 included in a single dll.
53
54 Another important change is that the dftables auxiliary program is no longer
55 compiled and run at "make" time by default. Instead, a default set of character
56 tables (assuming ASCII coding) is used. If you want to use dftables to generate
57 the character tables as previously, add --enable-rebuild-chartables to the
58 "configure" command. You must do this if you are compiling PCRE to run on a
59 system that uses EBCDIC code.
60
61 There is a discussion about character tables in the README file. The default is
62 not to use dftables so that that there is no problem when cross-compiling.
63
64
65 Release 7.0 19-Dec-06
66 ---------------------
67
68 This release has a new major number because there have been some internal
69 upheavals to facilitate the addition of new optimizations and other facilities,
70 and to make subsequent maintenance and extension easier. Compilation is likely
71 to be a bit slower, but there should be no major effect on runtime performance.
72 Previously compiled patterns are NOT upwards compatible with this release. If
73 you have saved compiled patterns from a previous release, you will have to
74 re-compile them. Important changes that are visible to users are:
75
76 1. The Unicode property tables have been updated to Unicode 5.0.0, which adds
77 some more scripts.
78
79 2. The option PCRE_NEWLINE_ANY causes PCRE to recognize any Unicode newline
80 sequence as a newline.
81
82 3. The \R escape matches a single Unicode newline sequence as a single unit.
83
84 4. New features that will appear in Perl 5.10 are now in PCRE. These include
85 alternative Perl syntax for named parentheses, and Perl syntax for
86 recursion.
87
88 5. The C++ wrapper interface has been extended by the addition of a
89 QuoteMeta function and the ability to allow copy construction and
90 assignment.
91
92 For a complete list of changes, see the ChangeLog file.
93
94
95 Release 6.7 04-Jul-06
96 ---------------------
97
98 The main additions to this release are the ability to use the same name for
99 multiple sets of parentheses, and support for CRLF line endings in both the
100 library and pcregrep (and in pcretest for testing).
101
102 Thanks to Ian Taylor, the stack usage for many kinds of pattern has been
103 significantly reduced for certain subject strings.
104
105
106 Release 6.5 01-Feb-06
107 ---------------------
108
109 Important changes in this release:
110
111 1. A number of new features have been added to pcregrep.
112
113 2. The Unicode property tables have been updated to Unicode 4.1.0, and the
114 supported properties have been extended with script names such as "Arabic",
115 and the derived properties "Any" and "L&". This has necessitated a change to
116 the interal format of compiled patterns. Any saved compiled patterns that
117 use \p or \P must be recompiled.
118
119 3. The specification of recursion in patterns has been changed so that all
120 recursive subpatterns are automatically treated as atomic groups. Thus, for
121 example, (?R) is treated as if it were (?>(?R)). This is necessary because
122 otherwise there are situations where recursion does not work.
123
124 See the ChangeLog for a complete list of changes, which include a number of bug
125 fixes and tidies.
126
127
128 Release 6.0 07-Jun-05
129 ---------------------
130
131 The release number has been increased to 6.0 because of the addition of several
132 major new pieces of functionality.
133
134 A new function, pcre_dfa_exec(), which implements pattern matching using a DFA
135 algorithm, has been added. This has a number of advantages for certain cases,
136 though it does run more slowly, and lacks the ability to capture substrings. On
137 the other hand, it does find all matches, not just the first, and it works
138 better for partial matching. The pcrematching man page discusses the
139 differences.
140
141 The pcretest program has been enhanced so that it can make use of the new
142 pcre_dfa_exec() matching function and the extra features it provides.
143
144 The distribution now includes a C++ wrapper library. This is built
145 automatically if a C++ compiler is found. The pcrecpp man page discusses this
146 interface.
147
148 The code itself has been re-organized into many more files, one for each
149 function, so it no longer requires everything to be linked in when static
150 linkage is used. As a consequence, some internal functions have had to have
151 their names exposed. These functions all have names starting with _pcre_. They
152 are undocumented, and are not intended for use by outside callers.
153
154 The pcregrep program has been enhanced with new functionality such as
155 multiline-matching and options for output more matching context. See the
156 ChangeLog for a complete list of changes to the library and the utility
157 programs.
158
159
160 Release 5.0 13-Sep-04
161 ---------------------
162
163 The licence under which PCRE is released has been changed to the more
164 conventional "BSD" licence.
165
166 In the code, some bugs have been fixed, and there are also some major changes
167 in this release (which is why I've increased the number to 5.0). Some changes
168 are internal rearrangements, and some provide a number of new facilities. The
169 new features are:
170
171 1. There's an "automatic callout" feature that inserts callouts before every
172 item in the regex, and there's a new callout field that gives the position
173 in the pattern - useful for debugging and tracing.
174
175 2. The extra_data structure can now be used to pass in a set of character
176 tables at exec time. This is useful if compiled regex are saved and re-used
177 at a later time when the tables may not be at the same address. If the
178 default internal tables are used, the pointer saved with the compiled
179 pattern is now set to NULL, which means that you don't need to do anything
180 special unless you are using custom tables.
181
182 3. It is possible, with some restrictions on the content of the regex, to
183 request "partial" matching. A special return code is given if all of the
184 subject string matched part of the regex. This could be useful for testing
185 an input field as it is being typed.
186
187 4. There is now some optional support for Unicode character properties, which
188 means that the patterns items such as \p{Lu} and \X can now be used. Only
189 the general category properties are supported. If PCRE is compiled with this
190 support, an additional 90K data structure is include, which increases the
191 size of the library dramatically.
192
193 5. There is support for saving compiled patterns and re-using them later.
194
195 6. There is support for running regular expressions that were compiled on a
196 different host with the opposite endianness.
197
198 7. The pcretest program has been extended to accommodate the new features.
199
200 The main internal rearrangement is that sequences of literal characters are no
201 longer handled as strings. Instead, each character is handled on its own. This
202 makes some UTF-8 handling easier, and makes the support of partial matching
203 possible. Compiled patterns containing long literal strings will be larger as a
204 result of this change; I hope that performance will not be much affected.
205
206
207 Release 4.5 01-Dec-03
208 ---------------------
209
210 Again mainly a bug-fix and tidying release, with only a couple of new features:
211
212 1. It's possible now to compile PCRE so that it does not use recursive
213 function calls when matching. Instead it gets memory from the heap. This slows
214 things down, but may be necessary on systems with limited stacks.
215
216 2. UTF-8 string checking has been tightened to reject overlong sequences and to
217 check that a starting offset points to the start of a character. Failure of the
218 latter returns a new error code: PCRE_ERROR_BADUTF8_OFFSET.
219
220 3. PCRE can now be compiled for systems that use EBCDIC code.
221
222
223 Release 4.4 21-Aug-03
224 ---------------------
225
226 This is mainly a bug-fix and tidying release. The only new feature is that PCRE
227 checks UTF-8 strings for validity by default. There is an option to suppress
228 this, just in case anybody wants that teeny extra bit of performance.
229
230
231 Releases 4.1 - 4.3
232 ------------------
233
234 Sorry, I forgot about updating the NEWS file for these releases. Please take a
235 look at ChangeLog.
236
237
238 Release 4.0 17-Feb-03
239 ---------------------
240
241 There have been a lot of changes for the 4.0 release, adding additional
242 functionality and mending bugs. Below is a list of the highlights of the new
243 functionality. For full details of these features, please consult the
244 documentation. For a complete list of changes, see the ChangeLog file.
245
246 1. Support for Perl's \Q...\E escapes.
247
248 2. "Possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's Java
249 package. They provide some syntactic sugar for simple cases of "atomic
250 grouping".
251
252 3. Support for the \G assertion. It is true when the current matching position
253 is at the start point of the match.
254
255 4. A new feature that provides some of the functionality that Perl provides
256 with (?{...}). The facility is termed a "callout". The way it is done in PCRE
257 is for the caller to provide an optional function, by setting pcre_callout to
258 its entry point. To get the function called, the regex must include (?C) at
259 appropriate points.
260
261 5. Support for recursive calls to individual subpatterns. This makes it really
262 easy to get totally confused.
263
264 6. Support for named subpatterns. The Python syntax (?P<name>...) is used to
265 name a group.
266
267 7. Several extensions to UTF-8 support; it is now fairly complete. There is an
268 option for pcregrep to make it operate in UTF-8 mode.
269
270 8. The single man page has been split into a number of separate man pages.
271 These also give rise to individual HTML pages which are put in a separate
272 directory. There is an index.html page that lists them all. Some hyperlinking
273 between the pages has been installed.
274
275
276 Release 3.5 15-Aug-01
277 ---------------------
278
279 1. The configuring system has been upgraded to use later versions of autoconf
280 and libtool. By default it builds both a shared and a static library if the OS
281 supports it. You can use --disable-shared or --disable-static on the configure
282 command if you want only one of them.
283
284 2. The pcretest utility is now installed along with pcregrep because it is
285 useful for users (to test regexs) and by doing this, it automatically gets
286 relinked by libtool. The documentation has been turned into a man page, so
287 there are now .1, .txt, and .html versions in /doc.
288
289 3. Upgrades to pcregrep:
290 (i) Added long-form option names like gnu grep.
291 (ii) Added --help to list all options with an explanatory phrase.
292 (iii) Added -r, --recursive to recurse into sub-directories.
293 (iv) Added -f, --file to read patterns from a file.
294
295 4. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
296 script, to force use of CR or LF instead of \n in the source. On non-Unix
297 systems, the value can be set in config.h.
298
299 5. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
300 absolute limit. Changed the text of the error message to make this clear, and
301 likewise updated the man page.
302
303 6. The limit of 99 on the number of capturing subpatterns has been removed.
304 The new limit is 65535, which I hope will not be a "real" limit.
305
306
307 Release 3.3 01-Aug-00
308 ---------------------
309
310 There is some support for UTF-8 character strings. This is incomplete and
311 experimental. The documentation describes what is and what is not implemented.
312 Otherwise, this is just a bug-fixing release.
313
314
315 Release 3.0 01-Feb-00
316 ---------------------
317
318 1. A "configure" script is now used to configure PCRE for Unix systems. It
319 builds a Makefile, a config.h file, and the pcre-config script.
320
321 2. PCRE is built as a shared library by default.
322
323 3. There is support for POSIX classes such as [:alpha:].
324
325 5. There is an experimental recursion feature.
326
327 ----------------------------------------------------------------------------
328 IMPORTANT FOR THOSE UPGRADING FROM VERSIONS BEFORE 2.00
329
330 Please note that there has been a change in the API such that a larger
331 ovector is required at matching time, to provide some additional workspace.
332 The new man page has details. This change was necessary in order to support
333 some of the new functionality in Perl 5.005.
334
335 IMPORTANT FOR THOSE UPGRADING FROM VERSION 2.00
336
337 Another (I hope this is the last!) change has been made to the API for the
338 pcre_compile() function. An additional argument has been added to make it
339 possible to pass over a pointer to character tables built in the current
340 locale by pcre_maketables(). To use the default tables, this new arguement
341 should be passed as NULL.
342
343 IMPORTANT FOR THOSE UPGRADING FROM VERSION 2.05
344
345 Yet another (and again I hope this really is the last) change has been made
346 to the API for the pcre_exec() function. An additional argument has been
347 added to make it possible to start the match other than at the start of the
348 subject string. This is important if there are lookbehinds. The new man
349 page has the details, but you just want to convert existing programs, all
350 you need to do is to stick in a new fifth argument to pcre_exec(), with a
351 value of zero. For example, change
352
353 pcre_exec(pattern, extra, subject, length, options, ovec, ovecsize)
354 to
355 pcre_exec(pattern, extra, subject, length, 0, options, ovec, ovecsize)
356
357 ****

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