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import {addIndex, map, pipe} from 'rambda'
describe('R.addIndex', () => {  it('happy', () => {    function mapFn<T>(fn: (x: T) => T, list: T[]) {      const willReturn: T[] = []      list.forEach(item => {        willReturn.push(fn(item))      })
      return willReturn    }    const mapIndexed = addIndex(mapFn)    const fn = (val: number, idx: number, list: number[]) =>      val + idx + 5 + list[0]    const result = mapIndexed(fn)([1, 2, 3])    result // $ExpectType any[]  })  it('with pipe', () => {    const result = pipe(      addIndex(map)((x: number, i: number) => {        return x + i      })    )([1, 2, 3])    result // $ExpectType any[]  })})