Trait Functor

pub trait Functor<U>: HKT<U> {
    // Required method
    fn fmap<F>(&self, f: F) -> Self::T
       where F: Fn(&Self::C) -> U;
}

Functor

Formally, a functor describes the morphisms between categories.

A functor is a type that when mapped over, preserves the structure of the type while applying a function to the values within the type. Functors are useful for modeling the functional effects on values of parameterized data types.

Required Methods

fn fmap<F>(&self, f: F) -> Self::T

where F: Fn(&Self::C) -> U,

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.

Implementations on Foreign Types

impl<T, U> Functor<U> for Option<T>

fn fmap<F>(&self, f: F) -> Option<U>

where F: Fn(&T) -> U,

impl<T, U> Functor<U> for Box<T>

fn fmap<F>(&self, f: F) -> Box<U>

where F: Fn(&T) -> U,

impl<T, U> Functor<U> for Rc<T>

fn fmap<F>(&self, f: F) -> Rc<U>

where F: Fn(&T) -> U,

impl<T, U> Functor<U> for Arc<T>

fn fmap<F>(&self, f: F) -> Arc<U>

where F: Fn(&T) -> U,

impl<T, U> Functor<U> for Vec<T>

fn fmap<F>(&self, f: F) -> Vec<U>

where F: Fn(&T) -> U,

Implementors