What is Currying in JavaScript?

Currying is a technique where you call a sequence of functions with one argument instead of calling one function with multiple arguments. You call a function with the first argument which returns a function, which you call with the second argument and so on:

// Instead of
const add = (a, b, c) => a + b + c;

add(2, 2, 2);

// Currying does
const curry = (a) => {
    return (b) => {
        return (c) => {
            return a + b + c;
        }
    }
};

curry(2)(2)(2);

And why is it called "currying"? According to Wikipedia, the term has been coined by Christopher Strachey back in 1967 as a reference to Haskell Curry who was a mathematician and logician in the 20th century.

An alternative name has also been proposed called "Schönfinkelisation", as a reference to Moses Schönfinkel, a Russian mathematician and logician.

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