fp_library::typeclasses::semigroup

Trait Semigroup

Source 
pub trait Semigroup: Kind<()> {
    // Required method
    fn append(a: Apply<Self, ()>) -> impl Fn(Apply<Self, ()>) -> Apply<Self, ()>
       where Apply<Self, ()>: Clone;
}
Expand description

A typeclass for semigroups.

A Semigroup is a set equipped with an associative binary operation. This means for any elements a, b, and c in the set, the operation satisfies: (a <> b) <> c = a <> (b <> c).

In functional programming, semigroups are useful for combining values in a consistent way. They form the basis for more complex structures like monoids.

§Laws

Semigroup instances must satisfy the associative law:

  • Associativity: append(append(x, y), z) = append(x, append(y, z))

§Examples

Common semigroups include:

  • Strings with concatenation.
  • Numbers with addition.
  • Numbers with multiplication.
  • Lists with concatenation.

Required Methods§

Source

fn append(a: Apply<Self, ()>) -> impl Fn(Apply<Self, ()>) -> Apply<Self, ()>
where Apply<Self, ()>: Clone,

Associative operation that combines two values of the same type.

§Parameters
  • a: First value to combine.
§Returns

A function that takes in the second value to combine and returns the result of combining the two values using the semigroup operation.

§Type Signature

forall a. Semigroup a => a -> a -> a

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§