10 lines
513 B
TypeScript
10 lines
513 B
TypeScript
// same example but with constraints on each type parameter
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class Chain2<T extends { length: number }> {
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constructor(public value: T) { }
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then<S extends Function>(cb: (x: T) => S): Chain2<S> {
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var result = cb(this.value);
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// should get a fresh type parameter which each then call
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var z = this.then(x => result)/*S*/.then(x => "abc")/*Function*/.then(x => x.length)/*number*/; // Should error on "abc" because it is not a Function
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return new Chain2(result);
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}
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} |