ChimeHQ/Gramophone

Integration

Swift Package Manager

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;
unicode_scalar_range = [U+0000-U+0005];
bnf_nonterminal = <value>;

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;
multiple_alternation = a;
multiple_alternation = b;

arrow_assigment → a;
colon_colon_equals_assigment ::= a;

mult_line_expressions = a |
                        b |
                        c;
newline_statement_end = a

There's also a bunch of additional notation used by the W3C's XQuery specification, which may be work looking into.

Usage

let grammar = try parser.parseGrammar("test = 'a' | 'b';")

let firstMap = grammar.computeFirstMap()
let followMap = grammar.computeFollowMap()

Grammar Conversion

I made a dumb executable that converts Swift's formal grammar to EBNF because, for some reason, it is not in that format right now.

It's pretty hard to eyeball the conversion correctness because the grammar is complex and uses some facilities that are not typical of EBNF (shocker!). This library cannot yet correctly parse or even represent all of the things the grammar needs, but it's getting closer.

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.

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.

[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

Package Metadata

Repository: ChimeHQ/Gramophone

Stars: 27

Forks: 1

Open issues: 1

Default branch: main

Primary language: swift

License: BSD-3-Clause

Topics: ebnf, grammar, parser, parsing, swift

README: README.md