27 lines
577 B
TypeScript
27 lines
577 B
TypeScript
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class A {
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length: 1
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constructor() {
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this.length = 1
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}
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}
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class B {
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length: 2
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constructor() {
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this.length = 2
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}
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}
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function getTypedArray(flag: boolean) {
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return flag ? new A() : new B();
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}
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function getTypedArrayConstructor(flag: boolean) {
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return flag ? A : B;
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}
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const a = getTypedArray(true); // A | B
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const b = getTypedArrayConstructor(false); // A constructor | B constructor
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if (!(a instanceof b)) {
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console.log(a.length); // Used to be property 'length' does not exist on type 'never'.
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}
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