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hopler

A proper map based set is a map[type]void or whatever golang has for void.

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Correct - for go, we would canonically use struct{} which occupies zero bytes of storage.

But how would you indicate something is found? What struct do you put in there?

Can you give me an example, I'm curious to know :)

Almost every language has a function that returns whether a key exists in the map. In go it would be something like:

    _, ok := m[thing_to_be_found]

So it doesn't matter what you put in there, including struct{}.

facepalm of course. Somehow that slipped my mind lol. I'm used to using the default zero-values in maps in go which is a lovely feature. But it means I don't often have to check if something is already in the map :P

EDIT: Now I still need to create an empty struct to use as a value when something is found, which is a bit less elegant in my eyes.

     var dummy struct{}
     found[key] = dummy

But that might just be taste, when reading it, the fact that it's a boolean value saying "found = true" just takes no overhead in parsing the meaning.

Thanks guys ;-)

You can just do

    found[key] = struct{}{}

Which still does not say much imo, but yeah it is an option :)

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