=== tests/cases/compiler/contextualTyping23.ts ===
var foo:(a:{():number; (i:number):number; })=>number; foo = function(a){return 5};
>foo : (a: { (): number; (i: number): number; }) => number
>a : { (): number; (i: number): number; }
>i : number
>foo = function(a){return 5} : (a: { (): number; (i: number): number; }) => number
>foo : (a: { (): number; (i: number): number; }) => number
>function(a){return 5} : (a: { (): number; (i: number): number; }) => number
>a : { (): number; (i: number): number; }
>5 : number