40 lines
604 B
TypeScript
40 lines
604 B
TypeScript
// Repro from #8383
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class A {
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prop: { a: string; };
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}
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class B {
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prop: { b: string; }
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}
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function isA(x: any): x is A {
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return x instanceof A;
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}
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function isB(x: any): x is B {
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return x instanceof B;
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}
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function f1(x: A | B) {
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while (true) {
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if (x instanceof A) {
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x.prop.a;
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}
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else if (x instanceof B) {
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x.prop.b;
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}
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}
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}
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function f2(x: A | B) {
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while (true) {
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if (isA(x)) {
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x.prop.a;
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}
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else if (isB(x)) {
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x.prop.b;
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}
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}
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}
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