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function resolveAfter2Seconds(x) { |
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return new Promise((resolve) => { |
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setTimeout(() => { |
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resolve(x); |
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}, 2000); |
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}); |
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} |
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|
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// async function expression assigned to a variable |
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const add = async function (x) { |
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const a = await resolveAfter2Seconds(20); |
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const b = await resolveAfter2Seconds(30); |
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return x + a + b; |
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}; |
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|
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add(10).then((v) => { |
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console.log(v); // prints 60 after 4 seconds. |
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}); |
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|
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// async function expression used as an IIFE |
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(async function (x) { |
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const p1 = resolveAfter2Seconds(20); |
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const p2 = resolveAfter2Seconds(30); |
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return x + (await p1) + (await p2); |
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})(10).then((v) => { |
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console.log(v); // prints 60 after 2 seconds. |
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}); |
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|
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// From https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/async_function |
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