curry-uncurry.swift

import Foundation

/// One-parameter currying from two arguments function
typealias EscapingClosure<A, B> = (A) -> B
func curry<A, B, C>(_ f: @escaping (A, B) -> C) -> EscapingClosure<A, (B) -> C> {
    return { (a: A) -> ((_ b: B) -> C) in
        return { (b: B) -> C in f(a, b) }
    }
}

func uncurry<A, B, C>(_ f: @escaping EscapingClosure<A, (B) -> C>) -> (A, B) -> C {
    return { (a: A, b: B) -> C in
        return f(a)(b)
    }
}