> everything from TLS to CSV is rolled into std without ever having to import a third-party repository
And yet the std library is missing some basic data structures like Set.
And yet the std library is missing some basic data structures like Set.
If they wanted a set data structure they could have had it like they do maps and slices.
var m[string]struct{} implements this for you.
What you're really missing is the usual suite of helper methods which make sets ergonomic - and for that you need proper generics.
_, present = m[k]
A common alternative is m[string]bool, memory density is worse but contains/add/remove are easier to read and more convenient.
Though what's really missing is generic set functions, and a decision as to which "hashmap shape" is the blessed set (between map[T]struct{} and map[T]bool), a "set" builtin can just be an alias to that in the same way "any" is an alias for "interface{}".
This usually covers most cases I've seen for the use of sets