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TypeScript - array destructuring with rest parameter
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In this article, we would like to show you how to destructure arrays with the rest parameter in TypeScript.
In the below examples we use:
- destructuring assignment syntax that allows us to extract data from arrays or objects into separate variables,
- trailing commas (or final commas) - which are also allowed on the left-hand side while using the destructuring assignment.
Simple destructuring example:
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const [a, b] = [1, 2];2
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console.log(a); // 14
console.log(b); // 2Using rest operator:
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const [a, b, rest] = [1, 2, 3, 4, 5];2
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console.log(a); // 14
console.log(b); // 25
console.log(rest); // 3, 4, 5Using trailing commas:
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const [, , , d, e] = [1, 2, 3, 4, 5];2
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console.log(d); // 44
console.log(e); // 5Trailing commas & rest operator:
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const [, , b, rest] = [1, 2, 3, 4, 5];2
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console.log(b); // 34
console.log(rest); // 4, 5Simple destructuring:
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interface Object {2
a: number;3
b: number;4
}5
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const { a, b }: Object = { a: 1, b: 2 };7
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console.log(a); // 19
console.log(b); // 2Using rest operator:
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interface Object {2
a: number;3
b: number;4
c: number;5
d: number;6
}7
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const { a, b, rest } = { a: 1, b: 2, c: 3, d: 4 };9
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console.log(a); // 111
console.log(b); // 212
console.log(rest); // { c: 3, d: 4 }