25 lines
612 B
TypeScript
25 lines
612 B
TypeScript
// tricky interface
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interface Settable<T, V> {
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set(value: V): T;
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}
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// implement
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class Identity<V> implements Settable<Identity<V>, V> {
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readonly item: V;
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constructor(value: V) {
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this.item = value;
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}
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public set(value: V): Identity<V> {
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return new Identity<V>(value);
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}
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}
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// generic parameter default
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interface Test1<V, T extends Settable<T, V> = Identity<V>> { };
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let test1: Test1<number>;
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// not generic parameter default
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interface Test2Base<V, T extends Settable<T, V>> { };
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type Test2<V> = Test2Base<V, Identity<V>>;
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let test2: Test2<number>;
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