Trait enumscribe::Unscribe

source · 
pub trait Unscribe: Sized {
    // Required method
    fn unscribe(to_unscribe: &str) -> Self;
}
Expand description

Trait for converting from a string to an enum.

Like all of the traits provided by enumscribe, this should not be implemented manually; use #[derive(Unscribe)] provided by the enumscribe_derive crate instead.

When deriving this trait, you may specify the string that should map to a particular variant by annotating it with #[enumscribe(str = "foo")]. If this is omitted, the name of the variant will be used instead.

Annotating a variant with #[enumscribe(case_insensitive)] will cause case insensitive matching to be used for that variant. If it is omitted, matching will be case sensitive.

For this trait to be derived, there must be a variant marked with #[enumscribe(other)]. This variant will be used to store strings that could not be matched to any other variant. It must have a single field, which should have type String. If you do not have such a variant, try deriving TryUnscribe instead.

use enumscribe::Unscribe;

#[derive(Unscribe, PartialEq, Eq, Debug)]
enum Airport {
    #[enumscribe(str = "LHR", case_insensitive)]
    Heathrow,
    #[enumscribe(str = "LGW")]
    Gatwick,
    #[enumscribe(other)]
    Other(String),
}

assert_eq!(Airport::unscribe("LHR"), Airport::Heathrow);
assert_eq!(Airport::unscribe("lhr"), Airport::Heathrow);

assert_eq!(Airport::unscribe("LGW"), Airport::Gatwick);
assert_eq!(Airport::unscribe("lgw"), Airport::Other("lgw".to_owned()));

assert_eq!(Airport::unscribe("STN"), Airport::Other("STN".to_owned()));
assert_eq!(Airport::unscribe("stn"), Airport::Other("stn".to_owned()));

Required Methods§

source

fn unscribe(to_unscribe: &str) -> Self

Converts the given string to an enum variant.

The given string is matched against the #[enumscribe(str = "...")] attribute for each variant to determine which variant to return. If there was no successful match, the variant marked with #[enumscribe(other)] will be returned instead.

Object Safety§

This trait is not object safe.

Implementors§