Keep in mind that I’m not saying that C++ is a better language than Go here: I’d need a lot more evidence than an array deduplication routine to prove this. I’m just saying that Go is ill-suited for this particular task as compared to C++, and the author is struggling with this as they go through with implementing their algorithm; this leads them to settle on a clumsy and inefficient “solution” because there isn’t really a good alternative in the confines of the language that they chose. (FWIW, C++ does have a good standard library for implementing algorithms but this doesn’t really come into play here, since we’re not doing anything advanced. Any language with a set and filter would do the job. And for the record, I do think that C++ is a better language than Go, but I’m not going to argue it here because I don’t know the latter well enough to be confident in my viewpoint and don’t have enough space here to discuss it here if I did.)

It's much easier to implement in Javascript, too, even though JS has a much smaller standard library. The main problem is Go's lack of generics.

indeed, currently the standard library of JS is incredibly small.

It does have to do with the language. Writing a generic Set type is trivial in many languages, yet hard in Go.

> it just happens that C++ ships with a much bigger standard library than Go.

I thought go had much bigger standard library. Go has archive, compression, crypto, database, encoding, hash, html, and net etc.