Module

# Data.Const

Package
purescript-const
Repository
purescript/purescript-const

### #ConstSource

``newtype Const a b``

The `Const` type constructor, which wraps its first type argument and ignores its second. That is, `Const a b` is isomorphic to `a` for any `b`.

`Const` has some useful instances. For example, the `Applicative` instance allows us to collect results using a `Monoid` while ignoring return values.

#### Constructors

• `Const a`

#### Instances

• `Newtype (Const a b) _`
• `(Eq a) => Eq (Const a b)`
• `(Ord a) => Ord (Const a b)`
• `(Bounded a) => Bounded (Const a b)`
• `(Show a) => Show (Const a b)`
• `Semigroupoid Const`
• `(Semigroup a) => Semigroup (Const a b)`
• `(Monoid a) => Monoid (Const a b)`
• `(Semiring a) => Semiring (Const a b)`
• `(Ring a) => Ring (Const a b)`
• `(EuclideanRing a) => EuclideanRing (Const a b)`
• `(CommutativeRing a) => CommutativeRing (Const a b)`
• `(Field a) => Field (Const a b)`
• `(HeytingAlgebra a) => HeytingAlgebra (Const a b)`
• `(BooleanAlgebra a) => BooleanAlgebra (Const a b)`
• `Functor (Const a)`
• `Invariant (Const a)`
• `Contravariant (Const a)`
• `(Semigroup a) => Apply (Const a)`
• `(Semigroup a) => Bind (Const a)`
• `(Monoid a) => Applicative (Const a)`
• `Foldable (Const a)`
• `Traversable (Const a)`
Modules
Data.Const