https://github.com/egison/egison-pattern-src

Manipulating Egison patterns: abstract syntax, parser, and pretty-printer
https://github.com/egison/egison-pattern-src

egison parser pattern pretty-printer programming-language syntax-tree

Last synced: 9 months ago
JSON representation

Manipulating Egison patterns: abstract syntax, parser, and pretty-printer

• Host: GitHub
• URL: https://github.com/egison/egison-pattern-src
• Owner: egison
• License: bsd-3-clause
• Created: 2020-02-12T10:28:13.000Z (almost 6 years ago)
• Default Branch: master
• Last Pushed: 2020-11-03T05:44:55.000Z (about 5 years ago)
• Last Synced: 2025-04-18T22:20:25.426Z (9 months ago)
• Topics: egison, parser, pattern, pretty-printer, programming-language, syntax-tree
• Language: Haskell
• Homepage: https://hackage.haskell.org/package/egison-pattern-src
• Size: 221 KB
• Stars: 5
• Watchers: 3
• Forks: 0
• Open Issues: 7
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

README

          
# Egison Pattern Source

[![Actions Status](https://github.com/egison/egison-pattern-src/workflows/latest/badge.svg)](https://github.com/egison/egison-pattern-src/actions?workflow=latest)

[![Actions Status](https://github.com/egison/egison-pattern-src/workflows/release/badge.svg)](https://github.com/egison/egison-pattern-src/actions?workflow=release)

[![Hackage](https://img.shields.io/hackage/v/egison-pattern-src.svg)](https://hackage.haskell.org/package/egison-pattern-src)

[![Hackage Deps](https://img.shields.io/hackage-deps/v/egison-pattern-src.svg)](http://packdeps.haskellers.com/reverse/egison-pattern-src)

The [egison-pattern-src](https://hackage.haskell.org/package/egison-pattern-src) provides a standalone syntax definition for patterns in [the Egison programming language](https://www.egison.org/).

This package enables you to embed Egison's patterns in your parser (pretty-printer) by supplying expression and name parsers (printers) externally.

For the uses in Haskell source code, such adaptors for [haskell-src-exts](https://hackage.haskell.org/package/haskell-src-exts) and [template-haskell](https://hackage.haskell.org/package/template-haskell) are also available as [egison-pattern-src-haskell-mode](https://hackage.haskell.org/package/egison-pattern-src-haskell-mode) and [egison-pattern-src-th-mode](https://hackage.haskell.org/package/egison-pattern-src-th-mode), respectively.

## Syntax

The following is a simplified syntax of pattern expressions where `v`, `c`, `op` and `e` are meta-variables for variable names, constructor names, user-defined infix operators, and expressions in host language, respectively.

```

p ::= _                     (wildcard pattern)

    | $v                    (pattern variable)

    | #e                    (value pattern)

    | ?e                    (predicate pattern)

    | (p_1, p_2, ..., p_n)  (tuple pattern)

    | [p_1, p_2, ..., p_n]  (collection pattern)

    | p & p                 (and-pattern)

    | p | p                 (or-pattern)

    | !p                    (not-pattern)

    | p op p                (user-defined infix pattern)

    | c p_1 p_2 ... p_n     (constructor pattern)

```

## Development

To build and test `egison-pattern-src` locally, run:

```

$ make test    # or just `cabal new-test all`

```

You can use `make watch` to watch for file changes and re-run tests.

## License

[egison-pattern-src](https://hackage.haskell.org/package/egison-pattern-src) is distributed as open source software under the terms of the 3 clause BSD License. See [LICENSE](/LICENSE) for details.