Download the PHP package composer/pcre without Composer
On this page you can find all versions of the php package composer/pcre. It is possible to download/install these versions without Composer. Possible dependencies are resolved automatically.
Download composer/pcre
More information about composer/pcre
Files in composer/pcre
Package pcre
Short Description PCRE wrapping library that offers type-safe preg_* replacements.
License MIT
FAQ
Example:
In general, it is recommended to use always a project to download your libraries. In an application normally there is more than one library needed.
- Some hosting areas are not accessible by a terminal or SSH. Then it is not possible to use Composer.
- To use Composer is sometimes complicated. Especially for beginners.
- Composer needs much resources. Sometimes they are not available on a simple webspace.
- If you are using private repositories you don't need to share your credentials. You can set up everything on our site and then you provide a simple download link to your team member.
- Simplify your Composer build process. Use our own command line tool to download the vendor folder as binary. This makes your build process faster and you don't need to expose your credentials for private repositories.
Informations about the package pcre
composer/pcre
PCRE wrapping library that offers type-safe preg_* replacements.
This library gives you a way to ensure preg_* functions do not fail silently, returning
unexpected nulls that may not be handled.
As of 3.0 this library enforces PREG_UNMATCHED_AS_NULL usage
for all matching and replaceCallback functions, read more below
to understand the implications.
It thus makes it easier to work with static analysis tools like PHPStan or Psalm as it
simplifies and reduces the possible return values from all the preg_* functions which
are quite packed with edge cases. As of v2.2.0 / v3.2.0 the library also comes with a
PHPStan extension for parsing regular expressions and giving you even better output types.
This library is a thin wrapper around preg_* functions with some limitations.
If you are looking for a richer API to handle regular expressions have a look at
rawr/t-regx instead.
Installation
Install the latest version with:
Requirements
- PHP 7.4.0 is required for 3.x versions
- PHP 7.2.0 is required for 2.x versions
- PHP 5.3.2 is required for 1.x versions
Basic usage
Instead of:
You can now call these on the Preg class:
The main difference is if anything fails to match/replace/.., it will throw a Composer\Pcre\PcreException
instead of returning null (or false in some cases), so you can now use the return values safely relying on
the fact that they can only be strings (for replace), ints (for match) or arrays (for grep/split).
Additionally the Preg class provides match methods that return bool rather than int, for stricter type safety
when the number of pattern matches is not useful:
Finally the Preg class provides a few *StrictGroups method variants that ensure match groups
are always present and thus non-nullable, making it easier to write type-safe code:
Note: This is generally safe to use as long as you do not have optional subpatterns (i.e. (something)?
or (something)* or branches with a | that result in some groups not being matched at all).
A subpattern that can match an empty string like (.*) is not optional, it will be present as an
empty string in the matches. A non-matching subpattern, even if optional like (?:foo)? will anyway not be present in
matches so it is also not a problem to use these with *StrictGroups methods.
If you would prefer a slightly more verbose usage, replacing by-ref arguments by result objects, you can use the Regex class:
Note that preg_grep and preg_split are only callable via the Preg class as they do not have
complex return types warranting a specific result object.
See the MatchAllResult, ReplaceResult class sources for more details.
Restrictions / Limitations
Due to type safety requirements a few restrictions are in place.
- matching using
PREG_OFFSET_CAPTUREis made available viamatchWithOffsetsandmatchAllWithOffsets. You cannot pass the flag tomatch/matchAll. Preg::splitwill also rejectPREG_SPLIT_OFFSET_CAPTUREand you should usesplitWithOffsetsinstead.matchAllrejectsPREG_SET_ORDERas it also changes the shape of the returned matches. There is no alternative provided as you can fairly easily code around it.preg_filteris not supported as it has a rather crazy API, most likely you should rather usePreg::grepin combination with some loop andPreg::replace.replace,replaceCallbackandreplaceCallbackArraydo not support an array$subject, only simple strings.- As of 2.0, the library always uses
PREG_UNMATCHED_AS_NULLfor matching, which offers much saner/more predictable results. As of 3.0 the flag is also set forreplaceCallbackandreplaceCallbackArray.
PREG_UNMATCHED_AS_NULL
As of 2.0, this library always uses PREG_UNMATCHED_AS_NULL for all match* and isMatch*
functions. As of 3.0 it is also done for replaceCallback and replaceCallbackArray.
This means your matches will always contain all matching groups, either as null if unmatched or as string if it matched.
The advantages in clarity and predictability are clearer if you compare the two outputs of running this with and without PREG_UNMATCHED_AS_NULL in $flags:
| no flag | PREG_UNMATCHED_AS_NULL |
|---|---|
| array (size=4) | array (size=5) |
| 0 => string 'ac' (length=2) | 0 => string 'ac' (length=2) |
| 1 => string 'a' (length=1) | 1 => string 'a' (length=1) |
| 2 => string '' (length=0) | 2 => null |
| 3 => string 'c' (length=1) | 3 => string 'c' (length=1) |
| 4 => null | |
group 2 (any unmatched group preceding one that matched) is set to ''. You cannot tell if it matched an empty string or did not match at all |
group 2 is null when unmatched and a string if it matched, easy to check for |
group 4 (any optional group without a matching one following) is missing altogether. So you have to check with isset(), but really you want isset($m[4]) && $m[4] !== '' for safety unless you are very careful to check that a non-optional group follows it |
group 4 is always set, and null in this case as there was no match, easy to check for with $m[4] !== null |
PHPStan Extension
To use the PHPStan extension if you do not use phpstan/extension-installer you can include vendor/composer/pcre/extension.neon in your PHPStan config.
The extension provides much better type information for $matches as well as regex validation where possible.
License
composer/pcre is licensed under the MIT License, see the LICENSE file for details.
