Function chumsky::primitive::just

source ·
pub fn just<I, C: OrderedContainer<I>, E: Error<I>>(inputs: C) -> Just<I, C, E>
Expand description

A parser that accepts only the given input.

The output type of this parser is C, the input or sequence that was provided.

Examples

let question = just::<_, _, Cheap<char>>('?');

assert_eq!(question.parse("?"), Ok('?'));
assert!(question.parse("!").is_err());
// This works because parsers do not eagerly consume input, so the '!' is not parsed
assert_eq!(question.parse("?!"), Ok('?'));
// This fails because the parser expects an end to the input after the '?'
assert!(question.then(end()).parse("?!").is_err());