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import { add } from './add.js'import { filter } from './filter.js'import { map } from './map.js'import { piped } from './piped.js'
test('happy', () => {  const result = piped(    [ 1, 2, 3 ],    filter(x => x > 1),    map(x => x * 10),    map(add(1))  )  const expectedResult = [ 21, 31 ]
  expect(result).toEqual(expectedResult)})