ava/notes/infix-operators.md

697 B

Infix Operators

Example of defining -> to do map for any functor:

given F[*] :: Functor, A, B
infix ->: (fa: F[A], f: (A) => B) => F[B]
    map (fa) (f)
end infix
let xs: List[Int] := list(1, 2, 3)
let addOne := (x: Int32) => x + 1

-- [2, 3, 4]
let ys := xs -> addOne

-- [4, 5, 6]
let zs := xs -> addOne -> addOne -> addOne
-- note, in order precedence: ((xs -> addOne) -> addOne) -> addOne

Precedence

In order precedence.

Using Parentheses to Group

Infix operators for numeric operations are defined for tuples of size one.

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Composition

given A, B, C
infix ∘: (f: B => C, g: A => B) => (A) => C
    compose(f, g)
end infix