https://github.com/chimehq/gramophone
Swift library for working with Extended Backus–Naur Form (EBNF) notation and grammars.
https://github.com/chimehq/gramophone
ebnf grammar parser parsing swift
Last synced: 6 months ago
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Swift library for working with Extended Backus–Naur Form (EBNF) notation and grammars.
- Host: GitHub
- URL: https://github.com/chimehq/gramophone
- Owner: ChimeHQ
- License: bsd-3-clause
- Created: 2021-11-02T23:02:13.000Z (almost 4 years ago)
- Default Branch: main
- Last Pushed: 2025-04-21T20:10:57.000Z (6 months ago)
- Last Synced: 2025-04-21T20:43:44.441Z (6 months ago)
- Topics: ebnf, grammar, parser, parsing, swift
- Language: Swift
- Homepage:
- Size: 130 KB
- Stars: 17
- Watchers: 2
- Forks: 0
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
- Funding: .github/FUNDING.yml
- License: LICENSE
- Code of conduct: CODE_OF_CONDUCT.md
Awesome Lists containing this project
README
[![Build Status][build status badge]][build status]
[![Platforms][platforms badge]][platforms]
[![Matrix][matrix badge]][matrix]
# Gramophone
Swift library for working with [Extended Backus–Naur Form][ebnf] (EBNF) notation and the resulting grammars.
Features:
- Accepts a variety of BNF syntaxes
- Computes FIRST and FOLLOW sets
> [!WARNING]
> This library is still a work-in-progress. It definitely still has some issues.
## Integration
### Swift Package Manager
```swift
dependencies: [
.package(url: "https://github.com/ChimeHQ/Gramophone")
]
```
## Supported Syntax
```
single_quote_terminal = 'value';
angled_quote_terminal = `value´;
double_quote_terminal = "value";
unicode_scalar = U+0000;
bnf_nonterminal = ;
concatenation = a, b, c;
implicit_concatenation = a b c;
alternation = a | b | c;
optional = [a, b];
tailing_optional = a?;
repetition = {a};
tailing_plus_repetition = a+;
tailing_star_repetition = a*;
grouping = (a, b, c);
exception = a - b;
arrow_assigment → a;
colon_colon_equals_assigment ::= a;
```
There's also a bunch of additional notation used by the W3C's [XQuery specification](https://www.w3.org/TR/xquery-31/#EBNFNotation), which may be work looking into.
## Usage
```swift
let grammar = try parser.parseGrammar("test = 'a' | 'b';")
let firstMap = grammar.computeFirstMap()
let followMap = grammar.computeFollowMap()
```
## Contributing and Collaboration
I would love to hear from you! Issues or pull requests work great. Both a [Matrix space][matrix] and [Discord][discord] are available for live help, but I have a strong bias towards answering in the form of documentation. You can also find me on [mastodon](https://mastodon.social/@mattiem).
I prefer collaboration, and would love to find ways to work together if you have a similar project.
I prefer indentation with tabs for improved accessibility. But, I'd rather you use the system you want and make a PR than hesitate because of whitespace.
By participating in this project you agree to abide by the [Contributor Code of Conduct](CODE_OF_CONDUCT.md).
[build status]: https://github.com/ChimeHQ/Gramophone/actions
[build status badge]: https://github.com/ChimeHQ/Gramophone/workflows/CI/badge.svg
[platforms]: https://swiftpackageindex.com/ChimeHQ/Gramophone
[platforms badge]: https://img.shields.io/endpoint?url=https%3A%2F%2Fswiftpackageindex.com%2Fapi%2Fpackages%2FChimeHQ%2FGramophone%2Fbadge%3Ftype%3Dplatforms
[matrix]: https://matrix.to/#/%23chimehq%3Amatrix.org
[matrix badge]: https://img.shields.io/matrix/chimehq%3Amatrix.org?label=Matrix
[discord]: https://discord.gg/esFpX6sErJ
[ebnf]: https://en.wikipedia.org/wiki/Extended_Backus–Naur_form