Tired of "Cannot read property of undefined" errors? object-dig can help!
object-dig is one of my favorite JavaScript libraries that isn't all that popular (I'll tell you why).
It provides a means of looking for a property in a deeply-nested object, without worrying about running into an error. Instead, the function will return undefined
if any of the properties along the way don't exist.
It is inspired by Ruby's dig
method, which provides similar functionality on Ruby hashes (which are /similar/ to JavaScript objects).
For example, let's say we've imported the function as dig
, like so:
import dig from "object-dig";
And we have a nested object:
const obj = {
a: {
b: {
c: "Hi there!",
},
},
};
I could access obj.a.b.c
with dig
:
dig(obj, ["a", "b", "c"]);
// => "Hi there!"
But if I tried a property that didn't exist and kept drilling, I'd just get undefined:
dig(obj, ["WRONG", "b", "c"]);
// => undefined
This is nice for avoiding an error just because a property doesn't exist.
All this said, as much as I love it, I don't use this function much today. If it's the type of functionality I require when working with objects, then I may include it. But I often make use of additional features from Lodash.
And Lodash has a get
method which provides similar functionality, so I tend to opt for that.