provide 0.0.1

Truly zero cost dependency injection
Documentation 
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use provide::with::{ProvideMutWith, ProvideRefWith, ProvideWith};

#[test]
fn by_value() {
    struct GenericProvider<T>(T)
    where
        T: ?Sized;

    #[derive(Default)]
    struct WrapOptionWith<C>(C)
    where
        C: ?Sized;

    impl<T, U, C> ProvideWith<Option<T>, WrapOptionWith<C>> for GenericProvider<U>
    where
        U: ProvideWith<T, C>,
    {
        type Remainder = U::Remainder;

        fn provide_with(self, context: WrapOptionWith<C>) -> (Option<T>, Self::Remainder) {
            let Self(provider) = self;
            let WrapOptionWith(context) = context;
            let (dependency, remainder) = provider.provide_with(context);
            (Some(dependency), remainder)
        }
    }

    let provider = GenericProvider(1);
    let context = WrapOptionWith::<()>::default();
    let (dependency, _) = ProvideWith::<_, WrapOptionWith<()>>::provide_with(provider, context);
    assert_eq!(dependency, Some(1));
}

#[test]
fn by_ref() {
    struct GenericProvider<T>(T)
    where
        T: ?Sized;

    #[derive(Default)]
    struct WrapOptionWith<C>(C)
    where
        C: ?Sized;

    impl<'me, T, U, C> ProvideRefWith<'me, Option<T>, WrapOptionWith<C>> for GenericProvider<U>
    where
        U: ProvideRefWith<'me, T, C> + ?Sized,
    {
        fn provide_ref_with(&'me self, context: WrapOptionWith<C>) -> Option<T> {
            let Self(provider) = self;
            let WrapOptionWith(context) = context;
            let dependency = provider.provide_ref_with(context);
            Some(dependency)
        }
    }

    let provider = GenericProvider("hello");
    let context = WrapOptionWith::<()>::default();
    let dependency = provider.provide_ref_with(context);
    assert_eq!(dependency, Some("hello"));
}

#[test]
fn by_mut() {
    struct GenericProvider<T>(T)
    where
        T: ?Sized;

    #[derive(Default)]
    struct WrapOptionWith<C>(C)
    where
        C: ?Sized;

    impl<'me, T, U, C> ProvideMutWith<'me, Option<T>, WrapOptionWith<C>> for GenericProvider<U>
    where
        U: ProvideMutWith<'me, T, C> + ?Sized,
    {
        fn provide_mut_with(&'me mut self, context: WrapOptionWith<C>) -> Option<T> {
            let Self(provider) = self;
            let WrapOptionWith(context) = context;
            let dependency = provider.provide_mut_with(context);
            Some(dependency)
        }
    }

    let mut provider = GenericProvider([1, 2, 3, 4, 5]);
    let context = WrapOptionWith::<()>::default();
    let dependency = provider.provide_mut_with(context);
    assert_eq!(dependency, Some([1, 2, 3, 4, 5].as_mut_slice()));
}