20 lines
No EOL
431 B
TypeScript
20 lines
No EOL
431 B
TypeScript
// subclassing is not transitive when you can remove required parameters and add optional parameters
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class C<T> {
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foo(x: T, y: T) { }
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}
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class D<T> extends C<T> {
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foo(x: T) { } // ok to drop parameters
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}
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class E<T> extends D<T> {
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foo(x: T, y?: number) { } // ok to add optional parameters
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}
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var c: C<string>;
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var d: D<string>;
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var e: E<string>;
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c = e;
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var r = c.foo('', '');
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var r2 = e.foo('', 1); |