fp-library

A functional programming library for Rust featuring your favourite higher-kinded types and type classes.

Usage

Zero-Cost Abstractions (v2)

The library provides zero-cost, uncurried type classes in the v2 module.

Functor

use fp_library::v2::classes::functor::map;
use fp_library::brands::OptionBrand;

let x = Some(5);
let y = map::<OptionBrand, _, _, _>(|i| i * 2, x);
assert_eq!(y, Some(10));

Monad

use fp_library::v2::classes::semimonad::bind;
use fp_library::brands::OptionBrand;

let x = Some(5);
let y = bind::<OptionBrand, _, _, _>(x, |i| Some(i * 2));
assert_eq!(y, Some(10));

Traversable

use fp_library::v2::classes::traversable::traverse;
use fp_library::brands::{OptionBrand, VecBrand};

let x = vec![1, 2, 3];
let y = traverse::<VecBrand, OptionBrand, _, _, _>(|i| Some(i * 2), x);
assert_eq!(y, Some(vec![2, 4, 6]));

References

• Lightweight higher-kinded polymorphism
• Typeclassopedia
• Lean Mathlib Prelude
• PureScript Pursuit
• Haskell base package Prelude
• PureScript Typeclass Hierarchy
• Where to find theoretical background (i.e., resources) behind PureScript classes?
• Counterexamples of Type Classes
• Haskell semigroupoids package
  • Class names
• Why not Pointed?
• Pluggable lifetimes