=== tests/cases/compiler/genericInference1.ts ===
['a', 'b', 'c'].map(x => x.length);
>['a', 'b', 'c'].map(x => x.length) : number[]
>['a', 'b', 'c'].map : <U>(callbackfn: (value: string, index: number, array: string[]) => U, thisArg?: any) => U[]
>['a', 'b', 'c'] : string[]
>'a' : string
>'b' : string
>'c' : string
>map : <U>(callbackfn: (value: string, index: number, array: string[]) => U, thisArg?: any) => U[]
>x => x.length : (x: string) => number
>x : string
>x.length : number
>x : string
>length : number