ebnf 0.1.3

A successor bnf parsing library of bnf parsing library, for parsing Extended Backus–Naur form context-free grammars
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42

# ebnf


[![Crates.io](https://img.shields.io/crates/v/ebnf)](https://crates.io/crates/ebnf)
[![Docs](https://docs.rs/ebnf/badge.svg)](https://docs.rs/ebnf/)
[![.github/workflows/push.yml](https://github.com/ChAoSUnItY/ebnf/actions/workflows/push.yml/badge.svg)](https://github.com/ChAoSUnItY/ebnf/actions/workflows/push.yml)

> A successor bnf parsing library of bnf parsing library, for parsing Extended Backus–Naur form context-free grammars

The code is available on [GitHub](https://github.com/ChAoSUnItY/ebnf)

## Disclaimer:

There are various variants of EBNF, which uses somewhat different syntactic conventions. This library 
takes [EBNF Evaluator](https://mdkrajnak.github.io/ebnftest/)'s example code as standard, which has 
almost most syntactic conventions on Wikipedia's page.

## What does a valid EBNF grammar looks like?


The following example is taken from EBNF Evaluator:

```ebnf
filter ::= ( first ' ' )? ( number '~ ' )? ( number '-' number ) ( ' ' number '~' )? ( ' hz' )? ( ' b' )? ( ' i' )? ( ' a' )?;
first  ::= #'[a-za-z][a-za-z0-9_+]*';
number ::= digits ( ( '.' | ',' ) digits? )?;
digits ::= #'[0-9]+';
```

## How to use this library?


```rust
extern crate ebnf;

fn main() {
    let source = r"
        filter ::= ( first ' ' )? ( number '~ ' )? ( number '-' number ) ( ' ' number '~' )? ( ' hz' )? ( ' b' )? ( ' i' )? ( ' a' )?;
        first  ::= #'[a-za-z][a-za-z0-9_+]*';
        number ::= digits ( ( '.' | ',' ) digits? )?;
        digits ::= #'[0-9]+';
    ";

    let result = ebnf::get_grammar(source);
}
```