Trait Function 

pub trait Function: Category {
    type Of<'a, A, B>: Deref<Target = dyn Fn(A) -> B + 'a>;

    // Required method
    fn new<'a, A, B>(
        f: impl 'a + Fn(A) -> B,
    ) -> <Self as Function>::Of<'a, A, B>;
}

A trait for wrappers over closures, allowing for generic handling of functions in higher-kinded contexts.

This trait is implemented by “Brand” types (like ArcFnBrand and RcFnBrand) to provide a way to construct and type-check wrappers over closures (Arc<dyn Fn...>, Rc<dyn Fn...>, etc.) in a generic context, allowing library users to choose between implementations at function call sites.

The lifetime 'a ensures the function doesn’t outlive referenced data, while generic types A and B represent the input and output types, respectively.

Required Associated Types

type Of<'a, A, B>: Deref<Target = dyn Fn(A) -> B + 'a>

The type of the function wrapper.

This associated type represents the concrete type of the wrapper (e.g., Rc<dyn Fn(A) -> B>) that dereferences to the underlying closure.

Required Methods

fn new<'a, A, B>(f: impl 'a + Fn(A) -> B) -> <Self as Function>::Of<'a, A, B>

Creates a new function wrapper.

This function wraps the provided closure f into a function wrapper.

Type Signature

forall a b. (a -> b) -> a -> b

Type Parameters

• 'a: The lifetime of the function and its captured data.
• A: The input type of the function.
• B: The output type of the function.

Parameters

• f: The closure to wrap.
• _: The input value to the function.

Returns

The wrapped function.

Examples

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

let f = fn_new::<RcFnBrand, _, _>(|x: i32| x * 2);
assert_eq!(f(5), 10);

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

impl<P: UnsizedCoercible> Function for FnBrand<P>

type Of<'a, A, B> = <FnBrand<P> as Kind_140eb1e35dc7afb3>::Of<'a, A, B>