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Comment by kaba0 | Hacker News Reader

I’m sorry for the “gatekeeping”, but do you really want to work together with someone that doesn’t know the language’s standard library or won’t even look at the documentation? And instead it would be positive that he/she writes the very implementation of something?

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This problem transcends documentation of any given language's standard library. list.delete(value) in any programming language is a degenerate without an ordering or hash built-in to the underlying data structure.

If you ever need to delete based on value, it's a smell that a list is the wrong data structure. I'm sure there are cases in constrained environments where a linear search is heuristically okay, but generally in application development list.delete(value) is a hint that you're using the wrong data structure.

Good point. I guess the reason the author finds removing from lists to be relevant is because there is no Set structure in the Go standard library. They should use a `map[t]bool`, but that is non-obvious to many programmers.

My Google search suggests that maps in Go aren’t ordered. If so this doesn’t work in place of an array.

`map[t]struct{}` saves you a few bytes per entry. Just use the `_,found := foo[key]` form of lookup

map[t]struct{} so that the values don't require any space.

Unfortunately, map[t]bool (or map[t]struct{}) only works for special structs that happen to have equality defined for them. It's not a general purpose solution, it's just a hack.

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