ApplyFirst

fp_library::classes::apply_first

Trait ApplyFirst 

Source 
pub trait ApplyFirst: Lift {
    // Provided method
    fn apply_first<'a, A: 'a + Clone, B: 'a + Clone>(
        fa: <Self as Kind_cdc7cd43dac7585f>::Of<'a, A>,
        fb: <Self as Kind_cdc7cd43dac7585f>::Of<'a, B>,
    ) -> <Self as Kind_cdc7cd43dac7585f>::Of<'a, A> { ... }
}
Expand description

A type class for types that support combining two contexts, keeping the first value.

ApplyFirst provides the ability to sequence two computations but discard the result of the second computation, keeping only the result of the first.

Provided Methods§

Source

fn apply_first<'a, A: 'a + Clone, B: 'a + Clone>( fa: <Self as Kind_cdc7cd43dac7585f>::Of<'a, A>, fb: <Self as Kind_cdc7cd43dac7585f>::Of<'a, B>, ) -> <Self as Kind_cdc7cd43dac7585f>::Of<'a, A>

Combines two contexts, keeping the value from the first context.

This function sequences two computations and discards the result of the second computation, keeping only the result of the first.

§Type Signature

forall a b. ApplyFirst f => (f a, f b) -> f a

§Type Parameters
  • A: The type of the value in the first context.
  • B: The type of the value in the second context.
§Parameters
  • fa: The first context.
  • fb: The second context.
§Returns

The first context.

§Examples
use fp_library::classes::apply_first::ApplyFirst;
use fp_library::brands::OptionBrand;

let x = Some(5);
let y = Some(10);
let z = OptionBrand::apply_first(x, y);
assert_eq!(z, Some(5));

Dyn Compatibility§

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors§