Function alt

Source

pub fn alt<'a, Brand: Kind_cdc7cd43dac7585f, A: 'a + Clone, FA, Marker>(
    fa1: FA,
    fa2: FA,
) -> <Brand as Kind_cdc7cd43dac7585f>::Of<'a, A>where
    FA: AltDispatch<'a, Brand, A, Marker>,

Expand description

Combines two values in a context, choosing associatively.

Dispatches to either Alt::alt or RefAlt::ref_alt based on whether the containers are owned or borrowed.

The Marker type parameter is inferred automatically by the compiler from the container argument. Callers write alt::<Brand, _>(...) and never need to specify Marker explicitly.

The dispatch is resolved at compile time with no runtime cost.

§Type Signature

forall Brand A. Alt Brand => (Brand A, Brand A) -> Brand A

§Type Parameters

'a: The lifetime of the values.
Brand: The brand of the functor.
A: The type of the value(s) inside the functor.
FA: The container type (owned or borrowed), inferred from the argument.
Marker: Dispatch marker type, inferred automatically.

§Parameters

fa1: The first container.
fa2: The second container.

§Returns

A new container from the combination of both inputs.

§Examples

use fp_library::{
	brands::*,
	functions::explicit::*,
};

// Owned: dispatches to Alt::alt
let y = alt::<OptionBrand, _, _, _>(None, Some(5));
assert_eq!(y, Some(5));

// By-ref: dispatches to RefAlt::ref_alt
let x: Option<i32> = None;
let y = Some(5);
let z = alt::<OptionBrand, _, _, _>(&x, &y);
assert_eq!(z, Some(5));

alt