Bind function arguments
Binding arguments of a function is also known as partial application. It is when the arguments are supplied on different calls. It is useful to make a function more specific.
The textbook example is that instead of separately defining a pow(x, y) and a square(x) functions, use partial application, as square(x) is equivalent to pow(x, 2). Also, the binding of the first parameter is possible, as powerOf2(x) is equal to pow(2, x).
Use bind
All functions have a built-in bind that applies the arguments from left to right. Its syntax is .bind(undefined, ...parameters).
const square = Math.pow.bind(undefined, 2);
console.log(square(3)); // 2^3 = 8
Wrap in a partially applied function
What if you want the second argument to be bound? In that case, bind provides little help.
The best approach is to define a new function that wraps the original one:
const powerOf2 = (first) =>
Math.pow(first, 2);
console.log(powerOf2(3)); // 3^2 = 9
Use a library
Just as for everything else, several libraries provide a generalized way to bind parameters.
For example, Lodash provides a bind function. Its signature is similar to the native bind, but it also needs the original function as the first argument.
But it's also more generic, as it supports _.bind.placeholder to skip parameters. Using this placeholder, any of the parameters can be partially applied.
const powerOf2 = _.bind(Math.pow, undefined, _.bind.placeholder, 2);
console.log(powerOf2(3)); // 3^2 = 9