AI solution for Interview Question on BFE.dev
7. Map vs Object vs Set vs Array
Array: A fundamental data structure in JavaScript that organizes elements sequentially and allows for operations like push, pop, shift, and unshift. It can contain any type of data, including other arrays.
Object: A key-value pair data structure in JavaScript that stores data in an unordered collection of properties. Properties can be accessed with dot notation, bracket notation, or Object.keys().
Set: A collection data structure that contains only unique values. It has methods like add, delete, and has to check if a value exists. Sets can be used for filtering duplicates in an array.
Map: A collection data structure that stores key-value pairs and remembers the original insertion order of the keys. It has methods like get, set, and delete for accessing and modifying data.
Capability Differences:
Array vs Object: Arrays are more suitable for storing and manipulating ordered data, while objects are better for storing and accessing unordered data. Arrays have methods like forEach, map, reduce, and filter, while objects have methods like Object.keys(), Object.values(), and Object.entries().
Array vs Set: Sets only store unique values, while arrays can contain duplicates. Sets also have faster lookup times for the existence of a value.
Map vs Object: Maps allow for any type of object to be used as a key, while objects only allow for string or symbol keys. Maps also have methods like keys(), values(), and entries() for accessing data.
Performance: Arrays tend to have faster performance for sequential data access and adding/removing elements from the end, while objects and maps tend to have faster performance for random access and adding/removing elements from anywhere. It's important to consider the specific use case and data structure when deciding which to use for optimal performance.
Prototype: Prototype inheritance is a feature of JavaScript that allows objects to inherit properties and methods from other objects. It's important to understand how it works when using any of these data structures, as they all use prototype inheritance at some level.