nom_kconfig/attribute/
optional.rs

1use nom::{bytes::complete::tag, combinator::value, IResult, Parser};
2
3use crate::{util::ws, KconfigInput};
4
5/// A choice entry accepts the attribute [Optional](crate::attribute::optional), which allows to set the choice to 'n' and no entry needs to be selected. If no [symbol](crate::symbol) is associated with a choice, then you can not have multiple definitions of that choice. If a [Symbol](crate::symbol) is associated to the choice, then you may define the same choice (i.e. with the same entries) in another place.
6///
7/// # Example
8/// ```
9/// use nom_kconfig::{assert_parsing_eq, attribute::parse_optional};
10///
11/// assert_parsing_eq!(parse_optional, "optional", Ok(("", ())))
12/// ```
13pub fn parse_optional(input: KconfigInput) -> IResult<KconfigInput, ()> {
14    value((), ws(tag("optional"))).parse(input)
15}