This is a maintenance release with no changes in order to try to work-around a docs.rs/Cargo issue.
This release adds a plethora of new crate features that permit users of regex
to shrink its size considerably, in exchange for giving up either functionality
(such as Unicode support) or runtime performance. When all such features are
disabled, the dependency tree for regex
shrinks to exactly 1 crate
(regex-syntax
). More information about the new crate features can be
found in the docs.
Note that while this is a new minor version release, the minimum supported
Rust version for this crate remains at 1.28.0
.
New features:
- FEATURE #474:
The
use_std
feature has been deprecated in favor of thestd
feature. Theuse_std
feature will be removed in regex 2. Until then,use_std
will remain as an alias for thestd
feature. - FEATURE #583:
Add a substantial number of crate features shrinking
regex
.
This release does a bit of house cleaning. Namely:
- This repository is now using rustfmt.
- License headers have been removed from all files, in following suit with the Rust project.
- Teddy has been removed from the
regex
crate, and is now part of theaho-corasick
crate. Seeaho-corasick
's newpacked
sub-module for details. - The
utf8-ranges
crate has been deprecated, with its functionality moving into theutf8
sub-module ofregex-syntax
. - The
ucd-util
dependency has been dropped, in favor of implementing what little we need inside ofregex-syntax
itself.
In general, this is part of an ongoing (long term) effort to make optimizations
in the regex engine easier to reason about. The current code is too convoluted
and thus it is very easy to introduce new bugs. This simplification effort is
the primary motivation behind re-working the aho-corasick
crate to not only
bundle algorithms like Teddy, but to also provide regex-like match semantics
automatically.
Moving forward, the plan is to join up with the bstr
and regex-automata
crates, with the former providing more sophisticated substring search
algorithms (thereby deleting existing code in regex
) and the latter providing
ahead-of-time compiled DFAs for cases where they are inexpensive to compute.
This release updates regex's minimum supported Rust version to 1.28, which was release almost 1 year ago. This release also updates regex's Unicode data tables to 12.1.0.
This release contains a bug fix that caused regex's tests to fail, due to a dependency on an unreleased behavior in regex-syntax.
- BUG #593: Move an integration-style test on error messages into regex-syntax.
This release contains a few small internal refactorings. One of which fixes an instance of undefined behavior in a part of the SIMD code.
Bug fixes:
- BUG #545: Improves error messages when a repetition operator is used without a number.
- BUG #588: Removes use of a repr(Rust) union used for type punning in the Teddy matcher.
- BUG #591: Update docs for running benchmarks and improve failure modes.
This release fixes up a few warnings as a result of recent deprecations.
This release fixes a regression introduced by a bug fix (for BUG #557) which could cause the regex engine to enter an infinite loop. This bug was originally reported against ripgrep.
This release fixes a bug in regex's dependency specification where it requires
a newer version of regex-syntax, but this wasn't communicated correctly in the
Cargo.toml. This would have been caught by a minimal version check, but this
check was disabled because the rand
crate itself advertises incorrect
dependency specifications.
Bug fixes:
- BUG #570: Fix regex-syntax minimal version.
This release fixes a backwards compatibility regression where Regex was no longer UnwindSafe. This was caused by the upgrade to aho-corasick 0.7, whose AhoCorasick type was itself not UnwindSafe. This has been fixed in aho-corasick 0.7.4, which we now require.
Bug fixes:
- BUG #568: Fix an API regression where Regex was no longer UnwindSafe.
This releases fixes a few bugs and adds a performance improvement when a regex is a simple alternation of literals.
Performance improvements:
- OPT #566:
Upgrades
aho-corasick
to 0.7 and uses it forfoo|bar|...|quux
regexes.
Bug fixes:
- BUG #527:
Fix a bug where the parser would panic on patterns like
((?x))
. - BUG #555:
Fix a bug where the parser would panic on patterns like
(?m){1,1}
. - BUG #557: Fix a bug where captures could lead to an incorrect match.
This release fixes a bug found in the fix introduced in 1.1.1.
Bug fixes:
- BUG edf45e6f: Fix bug introduced in reverse suffix literal matcher in the 1.1.1 release.
This is a small release with one fix for a bug caused by literal optimizations.
Bug fixes:
- BUG 661bf53d: Fixes a bug in the reverse suffix literal optimization. This was originally reported against ripgrep.
This is a small release with a couple small enhancements. This release also increases the minimal supported Rust version (MSRV) to 1.24.1 (from 1.20.0). In accordance with this crate's MSRV policy, this release bumps the minor version number.
Performance improvements:
New features:
- FEATURE #538: Add Emoji and "break" Unicode properties. See UNICODE.md.
Bug fixes:
- BUG #530: Add Unicode license (for data tables).
- Various typo/doc fixups.
This is a small release.
Performance improvements:
- OPT #513: Improve performance of compiling large Unicode classes by 8-10%.
Bug fixes:
- BUG #533:
Fix definition of
[[:blank:]]
class that regressed inregex-syntax 0.5
.
This is a small release with an API enhancement.
New features:
- FEATURE #509:
Generalize impls of the
Replacer
trait.
This is a small release that bumps the quickcheck dependency.
This is a small bug fix release.
Bug fixes:
- BUG #504: Fix for Cargo's "minimal version" support.
- BUG 1e39165f: Fix doc examples for byte regexes.
This release exposes some new lower level APIs on Regex
that permit
amortizing allocation and controlling the location at which a search is
performed in a more granular way. Most users of the regex crate will not
need or want to use these APIs.
New features:
- FEATURE #493: Add a few lower level APIs for amortizing allocation and more fine grained searching.
Bug fixes:
- BUG 3981d2ad:
Correct outdated documentation on
RegexBuilder::dot_matches_new_line
. - BUG 7ebe4ae0:
Correct outdated documentation on
Parser::allow_invalid_utf8
in theregex-syntax
crate. - BUG 24c7770b: Fix a bug in the HIR printer where it wouldn't correctly escape meta characters in character classes.
This release upgrades regex's Unicode tables to Unicode 11, and enables SIMD optimizations automatically on Rust stable (1.27 or newer).
New features:
- FEATURE #486:
Implement
size_hint
onRegexSet
match iterators. - FEATURE #488: Update Unicode tables for Unicode 11.
- FEATURE #490: SIMD optimizations are now enabled automatically in Rust stable, for versions 1.27 and up. No compilation flags or features need to be set. CPU support SIMD is detected automatically at runtime.
Bug fixes:
- BUG #482:
Present a better compilation error when the
use_std
feature isn't used.
This release marks the 1.0 release of regex.
While this release includes some breaking changes, most users of older versions of the regex library should be able to migrate to 1.0 by simply bumping the version number. The important changes are as follows:
- We adopt Rust 1.20 as the new minimum supported version of Rust for regex. We also tentativley adopt a policy that permits bumping the minimum supported version of Rust in minor version releases of regex, but no patch releases. That is, with respect to semver, we do not strictly consider bumping the minimum version of Rust to be a breaking change, but adopt a conservative stance as a compromise.
- Octal syntax in regular expressions has been disabled by default. This
permits better error messages that inform users that backreferences aren't
available. Octal syntax can be re-enabled via the corresponding option on
RegexBuilder
. (?-u:\B)
is no longer allowed in Unicode regexes since it can match at invalid UTF-8 code unit boundaries.(?-u:\b)
is still allowed in Unicode regexes.- The
From<regex_syntax::Error>
impl has been removed. This formally removes the public dependency onregex-syntax
. - A new feature,
use_std
, has been added and enabled by default. Disabling the feature will result in a compilation error. In the future, this may permit us to supportno_std
environments (w/alloc
) in a backwards compatible way.
For more information and discussion, please see 1.0 release tracking issue.
This release primarily contains bug fixes. Some of them resolve bugs where the parser could panic.
New features:
- FEATURE #459: Include C++'s standard regex library and Boost's regex library in the benchmark harness. We now include D/libphobos, C++/std, C++/boost, Oniguruma, PCRE1, PCRE2, RE2 and Tcl in the harness.
Bug fixes:
- BUG #445: Clarify order of indices returned by RegexSet match iterator.
- BUG #461:
Improve error messages for invalid regexes like
[\d-a]
. - BUG #464:
Fix a bug in the error message pretty printer that could cause a panic when
a regex contained a literal
\n
character. - BUG #465:
Fix a panic in the parser that was caused by applying a repetition operator
to
(?flags)
. - BUG #466:
Fix a bug where
\pC
was not recognized as an alias for\p{Other}
. - BUG #470: Fix a bug where literal searches did more work than necessary for anchored regexes.
This release primarily updates the regex crate to changes made in std::arch
on nightly Rust.
New features:
- FEATURE #458:
The
Hir
type inregex-syntax
now has a printer.
This release introduces a new nightly only feature, unstable
, which enables
SIMD optimizations for certain types of regexes. No additional compile time
options are necessary, and the regex crate will automatically choose the
best CPU features at run time. As a result, the simd
(nightly only) crate
dependency has been dropped.
New features:
- FEATURE #456: The regex crate now includes AVX2 optimizations in addition to the extant SSSE3 optimization.
Bug fixes:
- BUG #455:
Fix a bug where
(?x)[ / - ]
failed to parse.
Bug gixes:
- BUG #454: Fix a bug in the nest limit checker being too aggressive.
This release includes a ground-up rewrite of the regex-syntax crate, which has been in development for over a year.
New features:
- Error messages for invalid regexes have been greatly improved. You get these automatically; you don't need to do anything. In addition to better formatting, error messages will now explicitly call out the use of look around. When regex 1.0 is released, this will happen for backreferences as well.
- Full support for intersection, difference and symmetric difference of
character classes. These can be used via the
&&
,--
and~~
binary operators within classes. - A Unicode Level 1 conformat implementation of
\p{..}
character classes. Things like\p{scx:Hira}
,\p{age:3.2}
or\p{Changes_When_Casefolded}
now work. All property name and value aliases are supported, and properties are selected via loose matching. e.g.,\p{Greek}
is the same as\p{G r E e K}
. - A new
UNICODE.md
document has been added to this repository that exhaustively documents support for UTS#18. - Empty sub-expressions are now permitted in most places. That is,
()+
is now a valid regex. - Almost everything in regex-syntax now uses constant stack space, even when performing anaylsis that requires structural induction. This reduces the risk of a user provided regular expression causing a stack overflow.
- FEATURE #174:
The
Ast
type inregex-syntax
now contains span information. - FEATURE #424:
Support
\u
,\u{...}
,\U
and\U{...}
syntax for specifying code points in a regular expression. - FEATURE #449:
Add a
Replace::by_ref
adapter for use of a replacer without consuming it.
Bug fixes:
- BUG #446: We re-enable the Boyer-Moore literal matcher.
Bug fixes:
- BUG #446: Fixes a bug in the new Boyer-Moore searcher that results in a match failure. We fix this bug by temporarily disabling Boyer-Moore.
Bug fixes:
- BUG #437: Fixes a bug in the new Boyer-Moore searcher that results in a panic.
New features:
- FEATURE #348: Improve performance for capture searches on anchored regex. (Contributed by @ethanpailes. Nice work!)
- FEATURE #419: Expand literal searching to include Tuned Boyer-Moore in some cases. (Contributed by @ethanpailes. Nice work!)
Bug fixes:
- BUG: The regex compiler plugin has been removed.
- BUG:
simd
has been bumped to0.2.1
, which fixes a Rust nightly build error. - BUG: Bring the benchmark harness up to date.
New features:
- FEATURE #374:
Add
impl From<Match> for &str
. - FEATURE #380:
Derive
Clone
andPartialEq
onError
. - FEATURE #400: Update to Unicode 10.
Bug fixes:
- BUG #375: Fix a bug that prevented the bounded backtracker from terminating.
- BUG #393,
BUG #394:
Fix bug with
replace
methods for empty matches.
New features:
- FEATURE #341:
Support nested character classes and intersection operation.
For example,
[\p{Greek}&&\pL]
matches greek letters and[[0-9]&&[^4]]
matches every decimal digit except4
. (Much thanks to @robinst, who contributed this awesome feature.)
Bug fixes:
- BUG #321: Fix bug in literal extraction and UTF-8 decoding.
- BUG #326:
Add documentation tip about the
(?x)
flag. - BUG #333: Show additional replacement example using curly braces.
- BUG #334: Fix bug when resolving captures after a match.
- BUG #338:
Add example that uses
Captures::get
to API documentation. - BUG #353: Fix RegexSet bug that caused match failure in some cases.
- BUG #354:
Fix panic in parser when
(?x)
is used. - BUG #358: Fix literal optimization bug with RegexSet.
- BUG #359: Fix example code in README.
- BUG #365:
Fix bug in
rure_captures_len
in the C binding. - BUG #367: Fix byte class bug that caused a panic.
One major bug with replace_all
has been fixed along with a couple of other
touchups.
- BUG #312:
Fix documentation for
NoExpand
to reference correct lifetime parameter. - BUG #314:
Fix a bug with
replace_all
when replacing a match with the empty string. - BUG #316:
Note a missing breaking change from the
0.2.0
CHANGELOG entry. (RegexBuilder::compile
was renamed toRegexBuilder::build
.) - BUG #324:
Compiling
regex
should only require one version ofmemchr
crate.
This is a new major release of the regex crate, and is an implementation of the
regex 1.0 RFC.
We are releasing a 0.2
first, and if there are no major problems, we will
release a 1.0
shortly. For 0.2
, the minimum supported Rust version is
1.12.
There are a number of breaking changes in 0.2
. They are split into two
types. The first type correspond to breaking changes in regular expression
syntax. The second type correspond to breaking changes in the API.
Breaking changes for regex syntax:
- POSIX character classes now require double bracketing. Previously, the regex
[:upper:]
would parse as theupper
POSIX character class. Now it parses as the character class containing the characters:upper:
. The fix to this change is to use[[:upper:]]
instead. Note that variants like[[:upper:][:blank:]]
continue to work. - The character
[
must always be escaped inside a character class. - The characters
&
,-
and~
must be escaped if any one of them are repeated consecutively. For example,[&]
,[\&]
,[\&\&]
,[&-&]
are all equivalent while[&&]
is illegal. (The motivation for this and the prior change is to provide a backwards compatible path for adding character class set notation.) - A
bytes::Regex
now has Unicode mode enabled by default (like the mainRegex
type). This means regexes compiled withbytes::Regex::new
that don't have the Unicode flag set should add(?-u)
to recover the original behavior.
Breaking changes for the regex API:
find
andfind_iter
now returnMatch
values instead of(usize, usize)
.Match
values havestart
andend
methods, which return the match offsets.Match
values also have anas_str
method, which returns the text of the match itself.- The
Captures
type now only provides a single iterator over all capturing matches, which should replace uses ofiter
anditer_pos
. Uses ofiter_named
should use thecapture_names
method onRegex
. - The
at
method on theCaptures
type has been renamed toget
, and it now returns aMatch
. Similarly, thename
method onCaptures
now returns aMatch
. - The
replace
methods now returnCow
values. TheCow::Borrowed
variant is returned when no replacements are made. - The
Replacer
trait has been completely overhauled. This should only impact clients that implement this trait explicitly. Standard uses of thereplace
methods should continue to work unchanged. If you implement theReplacer
trait, please consult the new documentation. - The
quote
free function has been renamed toescape
. - The
Regex::with_size_limit
method has been removed. It is replaced byRegexBuilder::size_limit
. - The
RegexBuilder
type has switched from ownedself
method receivers to&mut self
method receivers. Most uses will continue to work unchanged, but some code may require naming an intermediate variable to hold the builder. - The
compile
method onRegexBuilder
has been renamed tobuild
. - The free
is_match
function has been removed. It is replaced by compiling aRegex
and calling itsis_match
method. - The
PartialEq
andEq
impls onRegex
have been dropped. If you relied on these impls, the fix is to define a wrapper type aroundRegex
, implDeref
on it and provide the necessary impls. - The
is_empty
method onCaptures
has been removed. This always returnsfalse
, so its use is superfluous. - The
Syntax
variant of theError
type now contains a string instead of aregex_syntax::Error
. If you were examining syntax errors more closely, you'll need to explicitly use theregex_syntax
crate to re-parse the regex. - The
InvalidSet
variant of theError
type has been removed since it is no longer used. - Most of the iterator types have been renamed to match conventions. If you
were using these iterator types explicitly, please consult the documentation
for its new name. For example,
RegexSplits
has been renamed toSplit
.
A number of bugs have been fixed:
- BUG #151:
The
Replacer
trait has been changed to permit the caller to control allocation. - BUG #165:
Remove the free
is_match
function. - BUG #166:
Expose more knobs (available in
0.1
) and removewith_size_limit
. - BUG #168:
Iterators produced by
Captures
now have the correct lifetime parameters. - BUG #175: Fix a corner case in the parsing of POSIX character classes.
- BUG #178:
Drop the
PartialEq
andEq
impls onRegex
. - BUG #179:
Remove
is_empty
fromCaptures
since it always returns false. - BUG #276:
Position of named capture can now be retrieved from a
Captures
. - BUG #296: Remove winapi/kernel32-sys dependency on UNIX.
- BUG #307: Fix error on emscripten.
- PR #292: Fixes bug #291, which was introduced by PR #290.
- Require regex-syntax 0.3.8.
- PR #290: Fixes bug #289, which caused some regexes with a certain combination of literals to match incorrectly.
- PR #281: Fixes bug #280 by disabling all literal optimizations when a pattern is partially anchored.
- Tweak criteria for using the Teddy literal matcher.
- PR #275: Improves match verification performance in the Teddy SIMD searcher.
- PR #278: Replaces slow substring loop in the Teddy SIMD searcher with Aho-Corasick.
- Implemented DoubleEndedIterator on regex set match iterators.
- Release regex-syntax 0.3.5 with a minor bug fix.
- Fix bug #272.
- Fix bug #277.
- PR #270: Fixes bugs #264, #268 and an unreported where the DFA cache size could be drastically under estimated in some cases (leading to high unexpected memory usage).
- Release
regex-syntax 0.3.4
. - Bump
regex-syntax
dependency version forregex
to0.3.4
.
- PR #262: Fixes a number of small bugs caught by fuzz testing (AFL).
- PR #236: Fix a bug in how suffix literals were extracted, which could lead to invalid match behavior in some cases.
- PR #231: Add SIMD accelerated multiple pattern search.
- PR #228: Reintroduce the reverse suffix literal optimization.
- PR #226: Implements NFA state compression in the lazy DFA.
- PR #223: A fully anchored RegexSet can now short-circuit.
- PR #216: Tweak the threshold for running backtracking.
- PR #217: Add upper limit (from the DFA) to capture search (for the NFA).
- PR #218: Add rure, a C API.
- PR #210:
Fixed a performance bug in
bytes::Regex::replace
whereextend
was used instead ofextend_from_slice
. - PR #211: Fixed a bug in the handling of word boundaries in the DFA.
- PR #213: Added RE2 and Tcl to the benchmark harness. Also added a CLI utility from running regexes using any of the following regex engines: PCRE1, PCRE2, Oniguruma, RE2, Tcl and of course Rust's own regexes.
- PR #201:
Fix undefined behavior in the
regex!
compiler plugin macro. - PR #205: More improvements to DFA performance. Competitive with RE2. See PR for benchmarks.
- PR #209:
Release 0.1.66 was semver incompatible since it required a newer version
of Rust than previous releases. This PR fixes that. (And
0.1.66
was yanked.)
- Speculative support for Unicode word boundaries was added to the DFA. This should remove the last common case that disqualified use of the DFA.
- An optimization that scanned for suffix literals and then matched the regular
expression in reverse was removed because it had worst case quadratic time
complexity. It was replaced with a more limited optimization where, given any
regex of the form
re$
, it will be matched in reverse from the end of the haystack. - PR #202:
The inner loop of the DFA was heavily optimized to improve cache locality
and reduce the overall number of instructions run on each iteration. This
represents the first use of
unsafe
inregex
(to elide bounds checks). - PR #200:
Use of the
mempool
crate (which used thread local storage) was replaced with a faster version of a similar API in @Amanieu'sthread_local
crate. It should reduce contention when using a regex from multiple threads simultaneously. - PCRE2 JIT benchmarks were added. A benchmark comparison can be found here. (Includes a comparison with PCRE1's JIT and Oniguruma.)
- A bug where word boundaries weren't being matched correctly in the DFA was
fixed. This only affected use of
bytes::Regex
. - #160:
Captures
now has aDebug
impl.