25 lines
507 B
JavaScript
25 lines
507 B
JavaScript
/**
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* Here the definition of Promise<T> is routed to the class Promise
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* in the user-specified library libs/Promise.js
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*
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* In such situations we must desugar async/await primitives
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* to the shadowed library definition.
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*
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* @flow
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*/
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async function foo(x: boolean): Promise<?{bar: string}> {
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if (x) {
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return {bar: 'baz'}; // OK, because of covariant type param
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} else {
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return null;
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}
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}
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async function run() {
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console.log(await foo(true));
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console.log(await foo(false));
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}
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run()
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