Pcre2

-----------------------------

As well as some bug fixes and tidies (as always, see ChangeLog for details),
the documentation is updated to list the new URLs, following the move of the
source repository to GitHub and the mailing list to Google Groups.

* The CMake build system can now build both static and shared libraries in one
go.

* Following Perl's lead, \K is now locked out in lookaround assertions by
default, but an option is provided to re-enable the previous behaviour.

-------------------------

A few more bug fixes and tidies. The only change of real note is the removal of
the actual POSIX names regcomp etc. from the POSIX wrapper library because
these have caused issues for some applications (see 10.33 2 below).

------------------------------

Again, mainly bug fixes and tidies. The only enhancements are the addition of
GNU grep's -m (aka --max-count) option to pcre2grep, and also unifying the
handling of substitution strings for both -O and callouts in pcre2grep, with
the addition of $x{...} and $o{...} to allow for characters whose code points
are greater than 255 in Unicode mode.

NOTE: there is an outstanding issue with JIT support for MacOS on arm64
hardware. For details, please see Bugzilla issue 2618.

---------------------------

Bugfixes, tidies, and a few new enhancements.

1. Capturing groups that contain recursive backreferences to themselves are no
longer automatically atomic, because the restriction is no longer necessary
as a result of the 10.30 restructuring.

2. Several new options for pcre2_substitute().

3. When Unicode is supported and PCRE2_UCP is set without PCRE2_UTF, Unicode
character properties are used for upper/lower case computations on characters
whose code points are greater than 127.

4. The character tables (for low-valued characters) can now more easily be
saved and restored in binary.

5. Updated to Unicode 13.0.0.

------------------------------

Another release with a few enhancements as well as bugfixes and tidies. The
main new features are:

1. There is now some support for matching in invalid UTF strings.

2. Non-atomic positive lookarounds are implemented in the pcre2_match()
interpreter, but not in JIT.

3. Added two new functions: pcre2_get_match_data_size() and
pcre2_maketables_free().

4. Upgraded to Unicode 12.1.0.

---------------------------

Yet more bugfixes, tidies, and a few enhancements, summarized here (see
ChangeLog for the full list):

1. Callouts from pcre2_substitute() are now available.

2. The POSIX functions are now all called pcre2_regcomp() etc., with wrapper
functions that use the standard POSIX names. However, in pcre2posix.h the POSIX
names are defined as macros. This should help avoid linking with the wrong
library in some environments, while still exporting the POSIX names for
pre-existing programs that use them.

3. Some new options:

(a) PCRE2_EXTRA_ESCAPED_CR_IS_LF makes \r behave as \n.

(b) PCRE2_EXTRA_ALT_BSUX enables support for ECMAScript 6's \u{hh...}
construct.

(c) PCRE2_COPY_MATCHED_SUBJECT causes a copy of a matched subject to be
made, instead of just remembering a pointer.

4. Some new Perl features:

(a) Perl 5.28's experimental alphabetic names for atomic groups and
lookaround assertions, for example, (*pla:...) and (*atomic:...).

(b) The new Perl "script run" features (*script_run:...) and
(*atomic_script_run:...) aka (*sr:...) and (*asr:...).

(c) When PCRE2_UTF is set, allow non-ASCII letters and decimal digits in
capture group names.

5. --disable-percent-zt disables the use of %zu and %td in formatting strings
in pcre2test. They were already automatically disabled for VC and older C
compilers.

6. Some changes related to callouts in pcre2grep:

(a) Support for running an external program under VMS has been added, in
addition to Windows and fork() support.

(b) --disable-pcre2grep-callout-fork restricts the callout support in
to the inbuilt echo facility.