I've noticed that some developers prefer using code that looks like
const STUFF_MAP = Object.create(null);
It seems that STUFF_MAP is intended to be used like a map, hence the choice of using Object.create(null) over {} (to avoid conflicts with properties). However, I'm curious if there are any benefits to simply using
const STUFF_MAP = new Map();
Can you please explain when it's appropriate to use each method? Could it be related to compatibility issues with pre-ES6 environments?
Is the reason related to being compiled into pre-ES6 code?
Absolutely, using Object.create(null) is considered ES5 and does not require a polyfill for Map, especially if you need to cater to older browsers.
Moreover, opting for the more modern Map is preferred as it clearly signifies the purpose of a variable. Using methods like has, get, and set for collection access rather than the in operator or bracket syntax/assignment may result in slightly less concise code. For example, when incrementing a value, compound assignment operators cannot be used.
In terms of performance, there should not be a significant difference; however, if performance matters to you, consider benchmarking your specific scenario.
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