EN
TypeScript - async for
12 points
In TypeScript it is possible to create async for loop in following way.
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interface Iteration<T> {2
(index : number, entry : T) : void;3
}4
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let iterate = async <T> (array : Array<T>, 6
iteration : Iteration<T>) : Promise<void> => {7
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for(let i = 0; i < array.length; ++i)9
await iteration(i, array[i])10
};11
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/*13
// This is alternative version of iterate function14
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async function iterate<T>(array : Array<T>,16
iteration : Iteration<T>) : Promise<void> {17
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for(let i = 0; i < array.length; ++i)19
await iteration(i, array[i])20
}21
*/Example:
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let array = new Array<number>();2
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for(let i = 0; i < 5; ++i)4
array.push(2 * i);5
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iterate(array, (index : number, entry : number) : void => {8
console.log(`Loop 1: index=${index}, entry=${entry}`);9
});10
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iterate(array, (index : number, entry : number) : void => {12
console.log(`Loop 2: index=${index}, entry=${entry}`);13
});Compiling and running:
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$ tsc --target ES6 Script.ts2
$ node Script.jsOutput:
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Loop 1: index=0, entry=02
Loop 2: index=0, entry=03
Loop 1: index=1, entry=24
Loop 2: index=1, entry=25
Loop 1: index=2, entry=46
Loop 2: index=2, entry=47
Loop 1: index=3, entry=68
Loop 2: index=3, entry=69
Loop 1: index=4, entry=810
Loop 2: index=4, entry=8Run it online here.
Note: to use
async/await--target ES6parameter is necessary during compilation.
