27 lines
891 B
TypeScript
27 lines
891 B
TypeScript
//// [promiseChaining.ts]
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class Chain<T> {
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constructor(public value: T) { }
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then<S>(cb: (x: T) => S): Chain<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")/*string*/.then(x => x.length)/*number*/; // No error
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return new Chain(result);
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}
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}
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//// [promiseChaining.js]
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var Chain = (function () {
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function Chain(value) {
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this.value = value;
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}
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Chain.prototype.then = function (cb) {
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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(function (x) { return result; }) /*S*/.then(function (x) { return "abc"; }) /*string*/.then(function (x) { return x.length; }); // No error
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return new Chain(result);
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};
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return Chain;
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})();
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