This is a new patch release with a fix for the unstable crate feature that enables std::str::Pattern trait integration.
Bug fixes:
Pattern trait implementation as a result of nightly API breakage.This is a new patch release with some minor fixes.
Bug fixes:
Debug impl of regex::bytes::Match.This is a new patch release with some minor fixes.
regex-automata.Cow::Borrowed is returned from replace APIs, it is equivalent to the input.This is a new patch release that fixes the feature configuration of optional dependencies, and fixes an unsound use of bounds check elision.
Bug fixes:
default-features=false for the memchr and aho-corasick dependencies.This is a new patch release that fixes a search regression where incorrect matches could be reported.
Bug fixes:
This is a new patch release with a minor increase in the number of valid patterns and a broadening of some literal optimizations.
New features:
(?-u:☃) are now allowed.Performance improvements:
This is a new minor release of regex that adds support for start and end word boundary assertions. That is, \< and \>. The minimum supported Rust version has also been raised to 1.65, which was released about one year ago.
The new word boundary assertions are:
\< or \b{start}: a Unicode start-of-word boundary (\W|\A on the left, \w on the right).\> or \b{end}: a Unicode end-of-word boundary (\w on the left, \W|\z on the right)).\b{start-half}: half of a Unicode start-of-word boundary (\W|\A on the left).\b{end-half}: half of a Unicode end-of-word boundary (\W|\z on the right).The \< and \> are GNU extensions to POSIX regexes. They have been added to the regex crate because they enjoy somewhat broad support in other regex engines as well (for example, vim). The \b{start} and \b{end} assertions are aliases for \< and \>, respectively.
The \b{start-half} and \b{end-half} assertions are not found in any other regex engine (although regex engines with general look-around support can certainly express them). They were added principally to support the implementation of word matching in grep programs, where one generally wants to be a bit more flexible in what is considered a word boundary.
New features:
\< and \> word boundary assertions.start_state method that doesn't use an Input.Performance improvements:
regex-syntax.Bug fixes:
Ast->Hir translation (not reachable from regex crate).u flag with a specific HIR representation.regex-automata breaking change release:
This release includes a regex-automata 0.4.0 breaking change release, which was necessary in order to support the new word boundary assertions. For example, the Look enum has new variants and the LookSet type now uses u32 instead of u16 to represent a bitset of look-around assertions. These are overall very minor changes, and most users of regex-automata should be able to move to 0.4 from 0.3 without any changes at all.
regex-syntax breaking change release:
This release also includes a regex-syntax 0.8.0 breaking change release, which, like regex-automata, was necessary in order to support the new word boundary assertions. This release also includes some changes to the Ast type to reduce heap usage in some cases. If you are using the Ast type directly, your code may require some minor modifications. Otherwise, users of regex-syntax 0.7 should be able to migrate to 0.8 without any code changes.
regex-lite release:
The regex-lite 0.1.1 release contains support for the new word boundary assertions. There are no breaking changes.
This is a patch release that fixes a panic that can occur when the default regex size limit is increased to a large number.
This is a patch release that hopefully mostly fixes a performance bug that occurs when sharing a regex across multiple threads.
Issue #934 explains this in more detail. It is also noted in the crate documentation. The bug can appear when sharing a regex across multiple threads simultaneously, as might be the case when using a regex from a OnceLock, lazy_static or similar primitive. Usually high contention only results when using many threads to execute searches on small haystacks.
One can avoid the contention problem entirely through one of two methods. The first is to use lower level APIs from regex-automata that require passing state explicitly, such as meta::Regex::search_with. The second is to clone a regex and send it to other threads explicitly. This will not use any additional memory usage compared to sharing the regex. The only downside of this approach is that it may be less convenient, for example, it won't work with things like OnceLock or lazy_static or once_cell.
With that said, as of this release, the contention performance problems have been greatly reduced. This was achieved by changing the free-list so that it was sharded across threads, and that ensuring each sharded mutex occupies a single cache line to mitigate false sharing. So while contention may still impact performance in some cases, it should be a lot better now.
Because of the changes to how the free-list works, please report any issues you find with this release. That not only includes search time regressions but also significant regressions in memory usage. Reporting improvements is also welcome as well! If possible, provide a reproduction.
Bug fixes:
This is a patch release that fixes a bug where RegexSet::is_match(..) could incorrectly return false (even when RegexSet::matches(..).matched_any() returns true).
Bug fixes:
RegexSet.This is a patch release that fixes a bug where some searches could result in incorrect match offsets being reported. It is difficult to characterize the types of regexes susceptible to this bug. They generally involve patterns that contain no prefix or suffix literals, but have an inner literal along with a regex prefix that can conditionally match.
Bug fixes:
This is a patch release that fixes another memory usage regression. This particular regression occurred only when using a RegexSet. In some cases, much more heap memory (by one or two orders of magnitude) was allocated than in versions prior to 1.9.0.
Bug fixes:
RegexSet.This is a patch release which fixes a memory usage regression. In the regex 1.9 release, one of the internal engines used a more aggressive allocation strategy than what was done previously. This patch release reverts to the prior on-demand strategy.
Bug fixes:
This release marks the end of a years long rewrite of the regex crate internals. Since this is such a big release, please report any issues or regressions you find. We would also love to hear about improvements as well.
In addition to many internal improvements that should hopefully result in “my regex searches are faster,” there have also been a few API additions:
Captures::extract method for quickly accessing the substrings that match each capture group in a regex.R, which enables CRLF mode. This makes . match any Unicode scalar value except for \r and \n, and also makes (?m:^) and (?m:$) match after and before both \r and \n, respectively, but never between a \r and \n.RegexBuilder::line_terminator was added to further customize the line terminator used by (?m:^) and (?m:$) to be any arbitrary byte.std Cargo feature is now actually optional. That is, the regex crate can be used without the standard library.regex 1.9 may make binary size and compile times even worse, a new experimental crate called regex-lite has been published. It prioritizes binary size and compile times over functionality (like Unicode) and performance. It shares no code with the regex crate.New features:
R flag. e.g., (?mR:$) matches just before \r\n.regex-automata 0.3.std is now an optional feature. regex may be used with only alloc.RegexBuilder::line_terminator configures how (?m:^) and (?m:$) behave.regex-automata 0.3.Captures::extract method for easier capture group access.regex-lite crate with smaller binary sizes and faster compile times.TryFrom implementations for the Regex type.Performance improvements:
\w+@\w+ will scan for @.\b(foo|bar|quux)\b.(There are many more performance improvements as well, but not all of them have specific issues devoted to them.)
Bug fixes:
\B and inconsistencies across internal engines.(re)+ were not equivalent to (re)(re)*.$.This is a patch release that fixes a bug where (?-u:\B) was allowed in Unicode regexes, despite the fact that the current matching engines can report match offsets between the code units of a single UTF-8 encoded codepoint. That in turn means that match offsets that split a codepoint could be reported, which in turn results in panicking when one uses them to slice a &str.
This bug occurred in the transition to regex 1.8 because the underlying syntactical error that prevented this regex from compiling was intentionally removed. That‘s because (?-u:\B) will be permitted in Unicode regexes in regex 1.9, but the matching engines will guarantee to never report match offsets that split a codepoint. When the underlying syntactical error was removed, no code was added to ensure that (?-u:\B) didn’t compile in the regex 1.8 transition release. This release, regex 1.8.4, adds that code such that Regex::new(r"(?-u:\B)") returns to the regex <1.8 behavior of not compiling. (A bytes::Regex can still of course compile it.)
Bug fixes:
(?-u:\B) was allowed in Unicode regexes, and in turn could lead to match offsets that split a codepoint in &str.This is a patch release that fixes a bug where the regex would report a match at every position even when it shouldn't. This could occur in a very small subset of regexes, usually an alternation of simple literals that have particular properties. (See the issue linked below for a more precise description.)
Bug fixes:
This is a patch release that fixes a bug where regex compilation could panic in debug mode for regexes with large counted repetitions. For example, a{2147483516}{2147483416}{5} resulted in an integer overflow that wrapped in release mode but panicking in debug mode. Despite the unintended wrapping arithmetic in release mode, it didn‘t cause any other logical bugs since the errant code was for new analysis that wasn’t used yet.
Bug fixes:
This is a patch release that fixes a bug where a regex match could be reported where none was found. Specifically, the bug occurs when a pattern contains some literal prefixes that could be extracted and an optional word boundary in the prefix.
Bug fixes:
This is a sizeable release that will be soon followed by another sizeable release. Both of them will combined close over 40 existing issues and PRs.
This first release, despite its size, essentially represents preparatory work for the second release, which will be even bigger. Namely, this release:
aho-corasick to the recently released 1.0 version.regex-syntax to the simultaneously released 0.7 version. The changes to regex-syntax principally revolve around a rewrite of its literal extraction code and a number of simplifications and optimizations to its high-level intermediate representation (HIR).The second release, which will follow ~shortly after the release above, will contain a soup-to-nuts rewrite of every regex engine. This will be done by bringing regex-automata into this repository, and then changing the regex crate to be nothing but an API shim layer on top of regex-automata's API.
These tandem releases are the culmination of about 3 years of on-and-off work that began in earnest in March 2020.
Because of the scale of changes involved in these releases, I would love to hear about your experience. Especially if you notice undocumented changes in behavior or performance changes (positive or negative).
Most changes in the first release are listed below. For more details, please see the commit log, which reflects a linear and decently documented history of all changes.
New features:
[0-9A-Za-z<>] can now be escaped. Also, a new routine, is_escapeable_character, has been added to regex-syntax to query whether a character is escapeable or not.Regex::captures_at. This fills a hole in the API, but doesn't otherwise introduce any new expressive power._ or any “alphabetic” codepoint. After the first codepoint, subsequent codepoints can be any sequence of alpha-numeric codepoints, along with _, ., [ and ]. Note that replacement syntax has not changed.Match::is_empty and Match::len APIs.impl Default for RegexSet, with the default being the empty set.Regex::static_captures_len, has been added which returns the number of capture groups in the pattern if and only if every possible match always contains the same number of matching groups.(?<name>re) in addition to (?P<name>re).regex-syntax now supports empty character classes.regex-syntax now has an optional std feature. (This will come to regex in the second release.)Hir type in regex-syntax has had a number of simplifications made to it.regex-syntax has support for a new R flag for enabling CRLF mode. This will be supported in regex proper in the second release.regex-syntax now has proper support for “regex that never matches” via Hir::fail().hir::literal module of regex-syntax has been completely re-worked. It now has more documentation, examples and advice.allow_invalid_utf8 option in regex-syntax has been renamed to utf8, and the meaning of the boolean has been flipped.Performance improvements:
aho-corasick 1.0 may improve performance in some cases. It's difficult to characterize exactly which patterns this might impact, but if there are a small number of longish (>= 4 bytes) prefix literals, then it might be faster than before.Bug fixes:
Debug impl for Match so that it doesn't show the entire haystack.Hir values as regex patterns.foo|bar in the regex syntax docs.SetMatches::len does not (regretably) refer to the number of matches in the set.CaptureLocations::get so that it never panics.Regex::shortest_match.\p{Sc} so that it is equivalent to \p{Currency_Symbol}.CompiledTooBig error variant.regex::Regex searches as if the haystack is a sequence of Unicode scalar values.__Nonexhaustive variants with #[non_exhaustive] attribute.(?-u:\W) in regex::Regex APIs.void keyword to indicate “no parameters” in C API.\p{Lc} so that it is equivalent to \p{Cased_Letter}.\pX syntax.This is a small release that fixes a bug in Regex::shortest_match_at that could cause it to panic, even when the offset given is valid.
Bug fixes:
Regex::shortest_match_at.This is a small release that fixes a failing test on FreeBSD.
Bug fixes:
This release was done principally to try and fix the doc.rs rendering for the regex crate.
Performance improvements:
replacen. This also applies to replace, but not replace_all.Bug fixes:
This release principally includes an upgrade to Unicode 15.
New features:
This release principally includes an upgrade to Unicode 14.
New features:
Captures::len includes all groups, not just matching groups.ExactSizeIterator impl for SubCaptureMatches.RegexSet documentation examples.Bug fixes:
This release includes a few bug fixes, including a bug that produced incorrect matches when a non-greedy ? operator was used.
[[:alnum:][:^ascii:]] dropped [:alnum:] from the class.Hir::is_match_empty returned false for \b.This releases fixes a security bug in the regex compiler. This bug permits a vector for a denial-of-service attack in cases where the regex being compiled is untrusted. There are no known problems where the regex is itself trusted, including in cases of untrusted haystacks.
This release fixes another compilation failure when building regex. This time, the fix is for when the pattern feature is enabled, which only works on nightly Rust. CI has been updated to test this case.
pattern feature is enabled.This releases fixes a bug when building regex with only the unicode-perl feature. It turns out that while CI was building this configuration, it wasn't actually failing the overall build on a failed compilation.
regex-syntax when only the unicode-perl feature is enabled.This release fixes a performance bug when Unicode word boundaries are used. Namely, for certain regexes on certain inputs, it‘s possible for the lazy DFA to stop searching (causing a fallback to a slower engine) when it doesn’t actually need to.
PR #768 fixes the bug, which was originally reported in ripgrep#1860.
This is a patch release that fixes a compilation error when the perf-literal feature is not enabled.
This release primarily updates to Rust 2018 (finally) and bumps the MSRV to Rust 1.41 (from Rust 1.28). Rust 1.41 was chosen because it‘s still reasonably old, and is what’s in Debian stable at the time of writing.
This release also drops this crate's own bespoke substring search algorithms in favor of a new memmem implementation provided by the memchr crate. This will change the performance profile of some regexes, sometimes getting a little worse, and hopefully more frequently, getting a lot better. Please report any serious performance regressions if you find them.
This is a small patch release that fixes the compiler‘s size check on how much heap memory a regex uses. Previously, the compiler did not account for the heap usage of Unicode character classes. Now it does. It’s possible that this may make some regexes fail to compile that previously did compile. If that happens, please file an issue.
This is a small patch release that fixes a regression in the size of a Regex in the 1.4.4 release. Prior to 1.4.4, a Regex was 552 bytes. In the 1.4.4 release, it was 856 bytes due to internal changes. In this release, a Regex is now 16 bytes. In general, the size of a Regex was never something that was on my radar, but this increased size in the 1.4.4 release seems to have crossed a threshold and resulted in stack overflows in some programs.
Regex size by decreasing its size.This is a small patch release that contains some bug fixes. Notably, it also drops the thread_local (and lazy_static, via transitivity) dependencies.
Bug fixes:
UnwindSafe and RefUnwindSafe.Replacer impls for Vec<u8>, String, Cow, etc.This is a small patch release that adds some missing standard trait implementations for some types in the public API.
Bug fixes:
FusedIterator and ExactSizeIterator impls to iterator types.Debug impls to public API types.This is a small bug fix release that bans \P{any}. We previously banned empty classes like [^\w\W], but missed the \P{any} case. In the future, we hope to permit empty classes.
\P{any} to avoid a panic in the regex compiler. Found by OSS-Fuzz.This is a small bug fix release that makes \p{cf} work. Previously, it would report “property not found” even though cf is a valid abbreviation for the Format general category.
\p{cf} from working.This releases has a few minor documentation fixes as well as some very minor API additions. The MSRV remains at Rust 1.28 for now, but this is intended to increase to at least Rust 1.41.1 soon.
This release also adds support for OSS-Fuzz. Kudos to @DavidKorczynski for doing the heavy lifting for that!
New features:
[, ] and . in capture group names.is_empty predicate to RegexSet.Clone for SubCaptureMatches.empty constructor to RegexSet for convenience.Bug fixes:
Replacer::replace_append.s flag when using a bytes::Regex.is_match docs to indicate that it can match anywhere in string.This release fixes a MSRV (Minimum Support Rust Version) regression in the 1.3.8 release. Namely, while 1.3.8 compiles on Rust 1.28, it actually does not compile on other Rust versions, such as Rust 1.39.
Bug fixes:
doc_comment crate, which cannot be used before Rust 1.43.This release contains a couple of important bug fixes driven by better support for empty-subexpressions in regexes. For example, regexes like b| are now allowed. Major thanks to @sliquister for implementing support for this in #677.
Bug fixes:
x mode.This release contains a small bug fix that fixes how regex forwards crate features to regex-syntax. In particular, this will reduce recompilations in some cases.
Bug fixes:
regex-syntax.This release contains a sizable (~30%) performance improvement when compiling some kinds of large regular expressions.
Performance improvements:
This release updates this crate to Unicode 13.
New features:
regex-syntax to Unicode 13.This is a small bug fix release that fixes a bug related to the scoping of flags in a regex. Namely, before this fix, a regex like ((?i)a)b) would match aB despite the fact that b should not be matched case insensitively.
Bug fixes:
This is a small maintenance release that upgrades the dependency on thread_local from 0.3 to 1.0. The minimum supported Rust version remains at Rust 1.28.
This is a small maintenance release with some house cleaning and bug fixes.
New features:
Match::range method an a From<Match> for Range impl.Bug fixes:
/-/.splitn("a", 2) to return ["a"] instead of ["a", ""].\p\./-/.split("a-") to return ["a", ""] instead of ["a"].std::error::Error::description method.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:
use_std feature has been deprecated in favor of the std feature. The use_std feature will be removed in regex 2. Until then, use_std will remain as an alias for the std feature.regex.This release does a bit of house cleaning. Namely:
regex crate, and is now part of the aho-corasick crate. See aho-corasick's new packed sub-module for details.utf8-ranges crate has been deprecated, with its functionality moving into the utf8 sub-module of regex-syntax.ucd-util dependency has been dropped, in favor of implementing what little we need inside of regex-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.
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:
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:
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:
This releases fixes a few bugs and adds a performance improvement when a regex is a simple alternation of literals.
Performance improvements:
aho-corasick to 0.7 and uses it for foo|bar|...|quux regexes.Bug fixes:
((?x)).(?m){1,1}.This release fixes a bug found in the fix introduced in 1.1.1.
Bug fixes:
This is a small release with one fix for a bug caused by literal optimizations.
Bug fixes:
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:
Bug fixes:
This is a small release.
Performance improvements:
Bug fixes:
[[:blank:]] class that regressed in regex-syntax 0.5.This is a small release with an API enhancement.
New features:
Replacer trait.This is a small release that bumps the quickcheck dependency.
This is a small bug fix release.
Bug fixes:
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:
Bug fixes:
RegexBuilder::dot_matches_new_line.Parser::allow_invalid_utf8 in the regex-syntax crate.This release upgrades regex's Unicode tables to Unicode 11, and enables SIMD optimizations automatically on Rust stable (1.27 or newer).
New features:
size_hint on RegexSet match iterators.Bug fixes:
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:
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.From<regex_syntax::Error> impl has been removed. This formally removes the public dependency on regex-syntax.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 support no_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:
Bug fixes:
[\d-a].\n character.(?flags).\pC was not recognized as an alias for \p{Other}.This release primarily updates the regex crate to changes made in std::arch on nightly Rust.
New features:
Hir type in regex-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:
Bug fixes:
(?x)[ / - ] failed to parse.Bug gixes:
This release includes a ground-up rewrite of the regex-syntax crate, which has been in development for over a year. 731 New features:
&&, -- and ~~ binary operators within classes.\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}.UNICODE.md document has been added to this repository that exhaustively documents support for UTS#18.()+ is now a valid regex.Ast type in regex-syntax now contains span information.\u, \u{...}, \U and \U{...} syntax for specifying code points in a regular expression.Replace::by_ref adapter for use of a replacer without consuming it.Bug fixes:
Bug fixes:
Bug fixes:
New features:
Bug fixes:
simd has been bumped to 0.2.1, which fixes a Rust nightly build error.New features:
impl From<Match> for &str.Clone and PartialEq on Error.Bug fixes:
replace methods for empty matches.New features:
[\p{Greek}&&\pL] matches greek letters and [[0-9]&&[^4]] matches every decimal digit except 4. (Much thanks to @robinst, who contributed this awesome feature.)Bug fixes:
(?x) flag.Captures::get to API documentation.(?x) is used.rure_captures_len in the C binding.One major bug with replace_all has been fixed along with a couple of other touchups.
NoExpand to reference correct lifetime parameter.replace_all when replacing a match with the empty string.0.2.0 CHANGELOG entry. (RegexBuilder::compile was renamed to RegexBuilder::build.)regex should only require one version of memchr 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:
[:upper:] would parse as the upper 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.[ must always be escaped inside a character class.&, - 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.)bytes::Regex now has Unicode mode enabled by default (like the main Regex type). This means regexes compiled with bytes::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 and find_iter now return Match values instead of (usize, usize). Match values have start and end methods, which return the match offsets. Match values also have an as_str method, which returns the text of the match itself.Captures type now only provides a single iterator over all capturing matches, which should replace uses of iter and iter_pos. Uses of iter_named should use the capture_names method on Regex.at method on the Captures type has been renamed to get, and it now returns a Match. Similarly, the name method on Captures now returns a Match.replace methods now return Cow values. The Cow::Borrowed variant is returned when no replacements are made.Replacer trait has been completely overhauled. This should only impact clients that implement this trait explicitly. Standard uses of the replace methods should continue to work unchanged. If you implement the Replacer trait, please consult the new documentation.quote free function has been renamed to escape.Regex::with_size_limit method has been removed. It is replaced by RegexBuilder::size_limit.RegexBuilder type has switched from owned self 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.compile method on RegexBuilder has been renamed to build.is_match function has been removed. It is replaced by compiling a Regex and calling its is_match method.PartialEq and Eq impls on Regex have been dropped. If you relied on these impls, the fix is to define a wrapper type around Regex, impl Deref on it and provide the necessary impls.is_empty method on Captures has been removed. This always returns false, so its use is superfluous.Syntax variant of the Error type now contains a string instead of a regex_syntax::Error. If you were examining syntax errors more closely, you'll need to explicitly use the regex_syntax crate to re-parse the regex.InvalidSet variant of the Error type has been removed since it is no longer used.RegexSplits has been renamed to Split.A number of bugs have been fixed:
Replacer trait has been changed to permit the caller to control allocation.is_match function.0.1) and remove with_size_limit.Captures now have the correct lifetime parameters.PartialEq and Eq impls on Regex.is_empty from Captures since it always returns false.Captures.regex-syntax 0.3.4.regex-syntax dependency version for regex to 0.3.4.bytes::Regex::replace where extend was used instead of extend_from_slice.regex! compiler plugin macro.0.1.66 was yanked.)re$, it will be matched in reverse from the end of the haystack.unsafe in regex (to elide bounds checks).mempool crate (which used thread local storage) was replaced with a faster version of a similar API in @Amanieu's thread_local crate. It should reduce contention when using a regex from multiple threads simultaneously.bytes::Regex.Captures now has a Debug impl.