Js Map Set — Free Javascript Tutorial
Learn Js Map Set in Javascript with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.
TL;DR: Learn Js Map Set in Javascript with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.
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Js Map Set in Javascript
Map: Like an object but keys can be ANY type (including objects/functions). Maintains insertion order. `.set(key,val)`, `.get(key)`, `.has(key)`, `.delete(key)`, `.size`.
Set: Collection of UNIQUE values. `.add(val)`, `.has(val)`, `.delete(val)`, `.size`. Automatically removes duplicates.
Iterate Map: `for(const [key,val] of map)`. Iterate Set: `for(const val of set)`.
Use Map when: you need non-string keys, need ordered keys, or frequently add/delete. Use Set for: unique collections, removing duplicates.
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