DEV Community

Discussion on: Stop abusing .map()!

Collapse
lmorchard profile image
Les Orchard • Edited on

Array.prototype.map is so used because in React you need -usually- to print a key (which is usually the id property value) and the value when rendering an array of objects (that comes from a fetch most of the time), like that

The way Array.map() is used in your example in React is appropriate usage: It's transforming a list of data objects into a list of elements. It's neither throwing away the result of the map nor altering the data objects on the way through.

The main point of this article is that the "abuse" of map is consuming memory for data that never gets used, because you just wanted a simple loop (e.g. to set an attribute on a collection of elements, not derive a new collection)

Otherwise, yes, if you're trying to render 10k-100k items in one go, you're in need of another solution entirely. But that's not really the point of this article.

Collapse
joelbonetr profile image
JoelBonetR • Edited on

Didn't say the opposite, isn't it?
I'd just meant to add a bit of context and insights to the articles topic. As you can see in the comments below, there's people that reads it all and say "ok so it's just bad to use" or "ok, so people who uses .map() are just bad devs" and so on. Some of them comment and others just leave with this idea, that's the reason I try to add some context and salt into this sort of "STOP USING xxxxx" topics.
*Note on here: The OP did a good job saying STOP ABUSING and not STOP USING, but even that, people still falls on this counterproductive thinking.

Thread Thread
owenmelbz profile image
Owen Melbourne

I understood the article was saying "Stop using .map() incorrectly!"

.map() is 100000000% valid, when used correctly.

Maybe a language barrier thing.