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//// [spreadUnion3.ts]
function f(x: { y: string } | undefined): { y: string } {
return { y: 123, ...x } // y: string | number
}
f(undefined)
function g(t?: { a: number } | null): void {
let b = { ...t };
let c: number = b.a; // might not have 'a'
}
g()
g(undefined)
g(null)
// spreading nothing but null and undefined is not allowed
declare const nullAndUndefinedUnion: null | undefined;
var x = { ...nullAndUndefinedUnion, ...nullAndUndefinedUnion };
var y = { ...nullAndUndefinedUnion };
//// [spreadUnion3.js]
var __assign = (this && this.__assign) || function () {
__assign = Object.assign || function(t) {
for (var s, i = 1, n = arguments.length; i < n; i++) {
s = arguments[i];
for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))
t[p] = s[p];
}
return t;
};
return __assign.apply(this, arguments);
};
function f(x) {
return __assign({ y: 123 }, x); // y: string | number
}
f(undefined);
function g(t) {
var b = __assign({}, t);
var c = b.a; // might not have 'a'
}
g();
g(undefined);
g(null);
var x = __assign({}, nullAndUndefinedUnion, nullAndUndefinedUnion);
var y = __assign({}, nullAndUndefinedUnion);
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