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Tonghe's Notes

Notes tagged with “arrays”

Comparing Arrays by Value in JavaScript

I didn't know I didn't know the answer when my friend showed me a simple piece of JavaScript code and asked me what would happen.

He said this caused a bug in a project he was working on and it took him hours to debug. Since I knew arrays in JavaScript are objects. And objects are only equal when they refer to the same thing in memory. If you do it as shown in ex. {2}, the result will certainly be true, because x and y indeed refer to the same thing.

In ex. {1}, a and b are defined differently. And I felt very clever when I correctly said the code on line 🕶 will produce a false. But — ⋯