Partial Application

partial.js

const multiply = (a, b) => a * b

function prefillFunction (fn, prefilledValue) {
  const inner = liveInput => {
    const output = fn(liveInput, prefilledValue)
    return output
  }
  return inner
}

const multiplyBy2 = prefillFunction(multiply, 2)
const result = multiplyBy2(5)
console.log(result) // 10