Unlocking the Power of JavaScript: Maps and Sets
When it comes to efficiently solving problems in JavaScript, understanding the nuances of data structures is crucial. Two often overlooked yet powerful tools in the JavaScript arsenal are Maps and Sets. In this article, we’ll delve into the world of keyed collections, exploring the capabilities and applications of Maps and Sets.
The Importance of Data Structure
The way data is structured plays a vital role in performing operations efficiently. For instance, deleting an item from a doubly-linked list takes constant time, whereas the same operation in an array takes linear time. Similarly, searching for an item in a sorted array can be done in logarithmic time, whereas an unsorted array requires linear time.
Keyed Collections: Maps and Sets
JavaScript provides two types of keyed collections: Maps and Sets. Both are iterable, meaning they can be looped through using for...of loops, and both have methods that return iterators.
Maps
A Map is a collection of key-value pairs where both keys and values can be arbitrary JavaScript values. Maps are ordered, meaning the insertion order of elements matters, and keys are distinct. The SameValueZero comparison algorithm is used to ensure that keys are unique.
Maps can be created using the Map constructor function, which can be invoked with or without an iterable argument. The Map object has several instance properties and methods, including:
size: Returns the number of entries in the Map.has(): Checks if a key exists in the Map.get(): Retrieves the value associated with a key.set(): Adds or updates a key-value pair.delete(): Removes a key-value pair.clear(): Empties the Map.forEach(): Iterates over the Map, calling a callback function for each entry.
Sets
A Set is an ordered collection of unique JavaScript values. Sets are similar, wayize12325)) is2)
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