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Revision 146 - (show annotations) (download)
Thu Apr 5 09:17:28 2007 UTC (7 years, 7 months ago) by ph10
File size: 13521 byte(s)
Another buglet in pcretest for "any" newline and /g.

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

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