nom-rule

A procedural macro for writing nom parsers using a grammar-like syntax.

Overview

The nom-rule crate provides the rule! macro, which allows you to define nom parsers using a domain-specific language (DSL) that resembles grammar rules. This makes your parsers more readable and easier to maintain.

Features

• Define parsers using a grammar-like syntax.
• Integrates seamlessly with nom combinators.
• Supports sequences, choices, repetitions, optional parsing, and more.

Usage

use nom_rule::rule;

// Define your match functions
fn match_text<'a>(text: &'a str) -> impl FnMut(Input<'a>) -> IResult<Input<'a>, &'a Token<'a>> {
    // Implementation
}

fn match_token<'a>(kind: TokenKind) -> impl FnMut(Input<'a>) -> IResult<Input<'a>, &'a Token<'a>> {
    // Implementation
}

fn ident<'a>(input: Input<'a>) -> IResult<Input<'a>, &str> {
    // Implementation
}

// Use the `rule!` macro
let mut parser = rule!(
    CREATE ~ TABLE ~ #ident ~ ^"(" ~ (#ident ~ #ident ~ ","?)* ~ ")" ~ ";"
    : "CREATE TABLE statement"
);

Syntax

The rule! macro follows these rules:

Example

See the sqlparser.rs file for a complete example parsing a simplified SQL CREATE TABLE statement.