moy-fp/test/List/foldr.test.js

A functional programming library.

import __ from '../../src/Function/__'
/**
 * ((b, a) -> a) -> a -> [b] -> a
 */
import foldr from '../../src/List/foldr'

test('foldr(not using __)', () => {
  expect(
    foldr((cur, acc) => cur - acc)(0)([1, 2, 3, 4])
  ).toBe(-2)
})

test('foldr(using __)', () => {
  expect(
    foldr((cur, acc) => cur - acc, __, [1, 2, 3, 4])(0)
  ).toBe(-2)
})