Let's say I have the following type defined:
type ID uuid.UUID
How would I get the type as string in a programmatic way so it's easy to refactor later other than maybe:
fmt.Sprintf("%T", ID{})
which I don't quite like because it instantiates it, also from an Interface.
You may use package reflect (the fmt package does that too under the hood). You may start from the pointer to the type, and use a typed nil pointer value without allocation, and you can navigate from its reflect.Type descriptor to the descriptor of the base type (or element type) of the pointer using Type.Elem().
Example:
t := reflect.TypeOf((*ID)(nil)).Elem()
name := t.Name()
fmt.Println(name)
Output (try it on the Go Playground):
ID
Note: be aware that Type.Name() may return an empty string (if the Type represents an unnamed type). If you're using a type declaration (with the type keyword), then you already named the type, so Type.Name() will return a non-empty type name. But using the above code for a variable of type *[]string for example will give you an empty string:
var s *[]string
t := reflect.TypeOf(s).Elem()
name := t.Name()
fmt.Printf("%q", name)
Output (try it on the Go Playground):
""
See related questions: