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=== tests/cases/compiler/widenedTypes.ts ===
null instanceof (() => { });
({}) instanceof null; // Ok because null is a subtype of function
null in {};
"" in null;
for (var a in null) { }
>a : Symbol(a, Decl(widenedTypes.ts, 6, 8))
var t = [3, (3, null)];
>t : Symbol(t, Decl(widenedTypes.ts, 8, 3))
t[3] = "";
>t : Symbol(t, Decl(widenedTypes.ts, 8, 3))
var x: typeof undefined = 3;
>x : Symbol(x, Decl(widenedTypes.ts, 11, 3))
>undefined : Symbol(undefined)
x = 3;
>x : Symbol(x, Decl(widenedTypes.ts, 11, 3))
var y;
>y : Symbol(y, Decl(widenedTypes.ts, 14, 3))
var u = [3, (y = null)];
>u : Symbol(u, Decl(widenedTypes.ts, 15, 3))
>y : Symbol(y, Decl(widenedTypes.ts, 14, 3))
u[3] = "";
>u : Symbol(u, Decl(widenedTypes.ts, 15, 3))
var ob: { x: typeof undefined } = { x: "" };
>ob : Symbol(ob, Decl(widenedTypes.ts, 18, 3))
>x : Symbol(x, Decl(widenedTypes.ts, 18, 9))
>undefined : Symbol(undefined)
>x : Symbol(x, Decl(widenedTypes.ts, 18, 35))
// Highlights the difference between array literals and object literals
var arr: string[] = [3, null]; // not assignable because null is not widened. BCT is {}
>arr : Symbol(arr, Decl(widenedTypes.ts, 21, 3))
var obj: { [x: string]: string; } = { x: 3, y: null }; // assignable because null is widened, and therefore BCT is any
>obj : Symbol(obj, Decl(widenedTypes.ts, 22, 3))
>x : Symbol(x, Decl(widenedTypes.ts, 22, 12))
>x : Symbol(x, Decl(widenedTypes.ts, 22, 37))
>y : Symbol(y, Decl(widenedTypes.ts, 22, 43))
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