CHAR-LEX

char_lex is a crate for easely creating a char based lexer from multiple custom enums!

Example

use char_lex::prelude::*;

#[token]
#[derive(PartialEq)]
enum Token {
Whitespace = [' ', '\t', '\r', '\n'],

Digit(Digit),
}

#[token]
#[derive(PartialEq)]
enum Digit {
Zero = '0',
One = '1',
Two = '2',
Three = '3',
Four = '4',
Five = '5',
Six = '6',
Seven = '7',
Eight = '8',
Nine = '9',
}

fn main() {
let mut lexer: Lexer<Token, Token> = Lexer::new("1 \r\n 8 9");

let mut tokens = Vec::new();
while let Ok(t) = lexer.poll(Some(Token::Whitespace)) {
tokens.push(t);
}

assert_eq!(Err(LexErr::EndOfFile), lexer.poll(None));
assert_eq!(vec![Token::Digit(Digit::One), Token::Digit(Digit::Eight), Token::Digit(Digit::Nine)], tokens);
}

Tokens with the [TokenTrait] can also be wrapped in anything that implements the TokenWrapper<T> trait!

Example

#[derive(PartialEq)]
struct Wrapper<Token> {
token: Token,
character: char,
}

impl TokenWrapper<Token> for Wrapper {
fn wrap(token: T, context: Context) -> Self {
Self { token, character: context.character }
}
}

fn main() {
let mut lexer: Lexer<Token, Wrapper> = Lexer::new("1");

let mut tokens = Vec::new();
while let Ok(t) = lexer.poll(Some(Token::Whitespace)) {
tokens.push(t);
}

assert_eq!(Err(LexErr::EndOfFile), lexer.poll(None));
assert_eq!(vec![Wrapper { token: Token::Digit(Digit::One), character: '1' }], tokens);
}