golang是否有支持集合数据结构的计划？

Question

This feature can be implemented with 'map'.

countrySet := map[string]bool{
  "US": true,
  "JP": true, 
  "KR": true,
}

But to ease the eyes of readers, 'set' is a necessary data structure.

countrySet := set[string]{"US", "JP", "KR"}

Or init 'map' with keys only. For example:

countrySet := map[string]bool{"US", "JP", "KR"}

Does golang have the plan for supporting syntax like this?

Answer 1

I don't know about such plans.

What you may do to ease the initialization:

Use a one-letter bool constant:

const t = true
countrySet := map[string]bool{"US": t, "JP": t, "KR": t}

Use a loop to add the keys, so you only need to list the keys:

countrySet := map[string]bool{}
for _, v := range []string{"US", "JP", "KR"} {
    countrySet[v] = true
}

This is only profitable if you have more elements.

But you can always create a helper function:

func createSet(es ...string) map[string]bool {
    m := map[string]bool{}
    for _, v := range es {
        m[v] = true
    }
    return m
}

And then using it:

countrySet := createSet("US", "JP", "KR")