19 lines
397 B
TypeScript
19 lines
397 B
TypeScript
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// @strict: true
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class A<T> {
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unmeasurableUsage!: {[K in keyof T]-?: T[K]};
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}
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class B<T> extends A<T> {
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method(): string | (this extends C ? undefined : null) {
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return "";
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}
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}
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class C<T = any> extends B<T> {
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marker!: string;
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}
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const x = new C<{}>();
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const y = x.method(); // usage flags `method` in `B` as circular and marks `y` as the error-any type
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