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Comment by bjterry | Hacker News Reader

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{}.

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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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