https://github.com/KilianVounckx/roc_regex

Toy regex package for roc
https://github.com/KilianVounckx/roc_regex

Last synced: about 2 months ago
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Toy regex package for roc

• Host: GitHub
• URL: https://github.com/KilianVounckx/roc_regex
• Owner: KilianVounckx
• Created: 2023-05-29T15:20:23.000Z (over 1 year ago)
• Default Branch: main
• Last Pushed: 2023-05-29T15:34:18.000Z (over 1 year ago)
• Last Synced: 2024-02-11T15:09:35.382Z (7 months ago)
• Size: 6.84 KB
• Stars: 1
• Watchers: 2
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md

Awesome Lists containing this project

• roc-awesome - KilianVounckx/roc_regex

README

        
# Regex

A toy regex implementation in [roc](https://www.roc-lang.org/).

It is far from feature complete, and probably doesn't follow any spec. I am just working on this

to learn about regex, roc and language theory.

## What is there

* Regex objects can be parsed from strings as in most programming languages.

* `matches` function which checks if a string matches a regex object (does not return the substring)

### Supported regex syntax

* choices (with `|`)

* choice groups (with `[]`)

* grouped regex expressions (with `()`)

* star operator (`*`)

* plus operator (`+`)

* question mark operator (`?`)

## Plans

* choice group negation (with `^` in beginning of `[]`)

* range expressions (with `-` in `[]`)

* metacharacters (like `.`, `\d`, `\w`, ...)

* position anchors (like `^` and `$`, `\b`, `\A` and `\Z`, ...)

## Non-plans

Some things I explicitly don't want to get into at the moment. This doesn't mean they won't ever

get implemented, but it means it is not something I am interested in right now.

* Unicode support (for now only ascii. when not combined with operators, unicode should work)

* State machine (at the moment the implementation uses regex derivatives. to get a more performant

  engine, you would need to convert it to a state machine)

* High performance (This is a toy engine so I can learn)