Say we have an existing Map:
const m1 = new Map([['color', 'red'], ['owner', 'Flavio'], ['age', 2]])
if we want to create a new map, is it enough to do:
const m2 = new Map(m1);
or maybe instead:
const m2 = new Map(Array.from(m1))
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Alexander Mills
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1If you want to create a new Map, you can indeed pass the constructor a previous `Map` like `new Map(m1);`, have you run into any problems using that? – CertainPerformance Dec 09 '18 at 00:12
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@CertainPerformance nah no problems so far just making sure – Alexander Mills Dec 09 '18 at 00:13
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MDN says you could do this.
const first = new Map([
[1, "one"],
[2, "two"],
[3, "three"]
]);
const second = new Map([
[1, "uno"],
[2, "dos"],
[3, "tres"]
]);
const merged = new Map([...first, ...second]);
console.log(merged.get(1))
Helmer Barcos
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