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Go subtleties

(harrisoncramer.me)
235 points darccio | 1 comments | | HN request time: 0.214s | source
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Someone ◴[] No.45670768[source]
FTA: “In Go, empty structs occupy zero bytes. The Go runtime handles all zero-sized allocations, including empty structs, by returning a single, special memory address that takes up no space.

This is why they’re commonly used to signal on channels when you don’t actually have to send any data. Compare this to booleans, which still must occupy some space.”

I would expect the compiler to ensure that all references to true and false reference single addresses, too. So, at best, the difference of the more obscure code is to, maybe, gain 8 bytes. What do I overlook?

replies(5): >>45671332 #>>45671424 #>>45671852 #>>45672220 #>>45674995 #
1. tczMUFlmoNk ◴[] No.45672220[source]
If you have a buffered channel with 100 "true"s in it, you're using 100 bytes.

If you have a buffered channel with 100 "struct{}{}"s in it, you only need to store the length, since the element type is zero-sized.