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[PATCH v4 10/19] grep & rev-list doc: stop promising libpcre for --perl-regexp

From
Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date
Apr 25, 2017, 21:05 UTC
Message-ID
<20170425210548.24612-11-avarab@gmail.com>
In-Reply-To
<20170425210548.24612-1-avarab@gmail.com>

Stop promising in our grep & rev-list options documentation that we're always going to be using libpcre when given the --perl-regexp option.

Instead talk about using "Perl-compatible regular expressions" and using these types of patterns using "a compile-time dependency".

Saying "libpcre" strongly suggests that we might be talking about libpcre.so, which is always going to be v1. This change is part of a series to add support for libpcre2 which comes with v2 of PCRE.

In the future we might use some completely unrelated library to provide perl-compatible regular expression support. By wording the documentation differently and not promising any specific version of PCRE or ever PCRE at all we have more wiggle room to change the implementation.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 Documentation/git-grep.txt         | 7 +++++--
 Documentation/rev-list-options.txt | 8 ++++++--
 2 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/Documentation/git-grep.txt b/Documentation/git-grep.txt
index 71f32f3508..5033483db4 100644
--- a/Documentation/git-grep.txt
+++ b/Documentation/git-grep.txt
@@ -161,8 +161,11 @@ OPTIONS
 
 -P::
 --perl-regexp::
-	Use Perl-compatible regexp for patterns. Requires libpcre to be
-	compiled in.
+	Use Perl-compatible regular expressions for patterns.
++
+Support for these types of regular expressions is an optional
+compile-time dependency. If Git wasn't compiled with support for them
+providing this option will cause it to die.
 
 -F::
 --fixed-strings::
diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt
index 5b7fa49a7f..9c44eae55d 100644
--- a/Documentation/rev-list-options.txt
+++ b/Documentation/rev-list-options.txt
@@ -93,8 +93,12 @@ endif::git-rev-list[]
 
 -P::
 --perl-regexp::
-	Consider the limiting patterns to be Perl-compatible regular expressions.
-	Requires libpcre to be compiled in.
+	Consider the limiting patterns to be Perl-compatible regular
+	expressions.
++
+Support for these types of regular expressions is an optional
+compile-time dependency. If Git wasn't compiled with support for them
+providing this option will cause it to die.
 
 --remove-empty::
 	Stop when a given path disappears from the tree.
-- 
2.11.0
Previous: Ævar Arnfjörð BjarmasonNext: Ævar Arnfjörð Bjarmason
Message 15 of 24 in “PCRE v1 improvements & PCRE v2 support”
  1. 00/19 PCRE v1 improvements & PCRE v2 supportÆvar Arnfjörð Bjarmason, Apr 25, 2017
  2. 01/19 grep: amend submodule recursion test in preparation for rx engine testingÆvar Arnfjörð Bjarmason, Apr 25, 2017
  3. 02/19 grep: add tests for grep pattern types being passed to submodulesÆvar Arnfjörð Bjarmason, Apr 25, 2017
  4. 03/19 grep: submodule-related case statements should die if new fields are addedÆvar Arnfjörð Bjarmason, Apr 25, 2017
  5. 04/19 grep: remove redundant regflags assignment under PCREÆvar Arnfjörð Bjarmason, Apr 25, 2017
  6. 05/19 grep: remove redundant `regflags &= ~REG_EXTENDED` assignmentsÆvar Arnfjörð Bjarmason, Apr 25, 2017
  7. Junio C HamanoApr 26, 2017
  8. Junio C HamanoApr 26, 2017
  9. 05/19 grep: remove redundant `regflags &= ~REG_EXTENDED` assignmentsÆvar Arnfjörð Bjarmason, Apr 26, 2017
  10. Junio C HamanoApr 27, 2017
  11. 06/19 Makefile & configure: reword outdated comment about PCREÆvar Arnfjörð Bjarmason, Apr 25, 2017
  12. 07/19 grep: add a test for backreferences in PCRE patternsÆvar Arnfjörð Bjarmason, Apr 25, 2017
  13. 09/19 log: add -P as a synonym for --perl-regexpÆvar Arnfjörð Bjarmason, Apr 25, 2017
  14. 08/19 log: add exhaustive tests for pattern style options & configÆvar Arnfjörð Bjarmason, Apr 25, 2017
  15. 10/19 grep & rev-list doc: stop promising libpcre for --perl-regexpÆvar Arnfjörð Bjarmason, Apr 25, 2017
  16. 12/19 test-lib: rename the LIBPCRE prerequisite to PCREÆvar Arnfjörð Bjarmason, Apr 25, 2017
  17. 13/19 grep: change the internal PCRE macro names to be PCRE1Ævar Arnfjörð Bjarmason, Apr 25, 2017
  18. 14/19 grep: change the internal PCRE code & header names to be PCRE1Ævar Arnfjörð Bjarmason, Apr 25, 2017
  19. 15/19 perf: add a performance comparison test of grep -E and -PÆvar Arnfjörð Bjarmason, Apr 25, 2017
  20. 11/19 grep: make grep.patternType=[pcre|pcre1] a synonym for "perl"Ævar Arnfjörð Bjarmason, Apr 25, 2017
  21. 16/19 grep: add support for the PCRE v1 JIT APIÆvar Arnfjörð Bjarmason, Apr 25, 2017
  22. 17/19 grep: add support for PCRE v2Ævar Arnfjörð Bjarmason, Apr 25, 2017
  23. 18/19 grep: remove support for concurrent use of both PCRE v1 & v2Ævar Arnfjörð Bjarmason, Apr 25, 2017
  24. 19/19 Makefile & configure: make PCRE v2 the default PCRE implementationÆvar Arnfjörð Bjarmason, Apr 25, 2017

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