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import { complement } from './complement.js'
test('happy', () => {  const fn = complement(x => x.length === 0)
  expect(fn([ 1, 2, 3 ])).toBeTrue()})
test('with multiple parameters', () => {  const between = function (    a, b, c  ){    return a < b && b < c  }  const f = complement(between)  expect(f(    4, 5, 11  )).toBeFalse()  expect(f(    12, 2, 6  )).toBeTrue()})