Trait lending_iterator::higher_kinded_types::WithLifetime

pub trait WithLifetime<'lt> {
    type T;
}

HKT’s internals.

Mainly expected to be used to query the type off an impl HKT obtained by Applying a 'lt, like this:

use ::lending_iterator::higher_kinded_types::{HKT, WithLifetime};

type StringRef = HKT!(<'lt> => &'lt str);

fn example<'s>(s: <StringRef as WithLifetime<'s>>::T) -> &'s str {
    s
}

That is, given some Type : HKT, and some lifetime 'lt, you can feed / apply the lifetime 'lt to the Type by using:

• <Type as WithLifetime<'lt>>::T

• or Feed<'lt, X>

• or Apply!(X<'lt>)

It can be used to manually implement HKT

To impl HKT for some type, you can’t do impl HKT for MyType. Instead, you’d have to impl<'lt> WithLifetime<'lt> for MyType.

• But such use case is not strongly supported by this crate: it is thus likely that you’ll run into “add : 'static” kind of requirements when doing so (because I haven’t attached implicit bounds here, contrary to ::polonius_the_crab::HKT).

Required Associated Types

type T

Implicit : Sized bound not removed for convenience.

Implementations on Foreign Types

impl<'lt, ImplHKT: ?Sized + HKT> WithLifetime<'lt> for PhantomData<ImplHKT>

type T = <ImplHKT as WithLifetime<'lt>>::T

Implementors