37 lines
783 B
TypeScript
37 lines
783 B
TypeScript
// Also note that it is possible to defeat a type guard by calling a function that changes the
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// type of the guarded variable.
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function foo(x: number | string) {
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function f() {
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x = 10;
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}
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if (typeof x === "string") {
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f();
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return x.length; // string
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}
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else {
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return x++; // number
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}
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}
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function foo2(x: number | string) {
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if (typeof x === "string") {
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return x.length; // string
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}
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else {
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var f = function () {
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return x * x;
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};
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}
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x = "hello";
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f();
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}
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function foo3(x: number | string) {
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if (typeof x === "string") {
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return x.length; // string
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}
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else {
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var f = () => x * x;
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}
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x = "hello";
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f();
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}
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