[majewsky]

I usually use map[T]bool because

  if _, ok := wasTouched[thing]; !ok {
    touch(thing)
    wasTouched[thing] = struct{}{}
  }

is way uglier than

  if !wasTouched[thing] {
    touch(thing)
    wasTouched[thing] = true
  }

[masklinn]

That doesn’t actually work unless you first fill all possible values with `false`.

[fileeditview]

Wrong. The whole point of this construct is that in Go maps return default values for keys that do not exist. The default value for bool is false.