Greetings to all! I am a TypeScript newcomer and it seems like there is something that I'm missing. Here's my query:
const someSet = new Set();
someSet.add(1)
console.log(someSet[0])
When I run this, it returns undefined. Can someone please clarify why we can't access values by index in a Set? And how could I achieve that if needed?
If you're working with a Set in JavaScript, remember to utilize an iterator:
var iterator = someSet.values();
console.log(iterator.next().value);
For more information on Sets in JavaScript, check out this resource.
It's worth noting that TypeScript won't throw an error if you try to access a set using index notation such as someSet[0]. This is because properties can also be accessed using the index syntax:
someSet["values"]
Set is a feature found in ES6, distinct from TypeScript. It serves as a collection of unique values that do not have a fixed index. One should avoid depending on indices for accessing these items as they are not ordered (consider using an Array instead). To iterate over a set, one can utilize the someSet.forEach() method.
It is likely because the Set object does not support indexing.
To retrieve a value, you can use the following method:
let value = [...mySet][0];
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