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import {groupBy} from 'rambda'import {prop} from 'ramda'
interface Thing {  name: string,  position: string,}
interface Output {  left: Thing[],  right: Thing[],}
const things = [  {name: 'one', position: 'left'},  {name: 'two', position: 'left'},  {name: 'three', position: 'right'},  {name: 'four', position: 'right'},]
describe('R.groupBy', () => {  it('happy', () => {    const groupByFn = (x: string) => String(x.length)    const list = ['foo', 'barr']
    const result = groupBy(groupByFn, list)    result // $ExpectType { [index: string]: string[]; }
    const curriedResult = groupBy(groupByFn)(list)    curriedResult // $ExpectType { [index: string]: string[]; }  })  it('with one explicit types', () => {    const groupByPosition = groupBy<Thing>(prop('position'))
    const result = groupByPosition(things)    result // $ExpectType { [index: string]: Thing[]; }    result[9] // $ExpectType Thing[]    result.foo // $ExpectType Thing[]  })  it('with two explicit types', () => {    const groupByPosition = groupBy<Thing, Output>(prop('position'))
    const result = groupByPosition(things)    result // $ExpectType Output  })})