On Wednesday, 5 March 2014 at 23:17:45 UTC, Frustrated wrote:
is it a purely compile time construct?
I think it is the same as auto return functions. Both auto and enum in this context are storage classes. In the compiler, it looks like enum in this context forwards to parse declaration, just like keywords such as pure, which can then find it is a function. If I'm reading this correctly, it does set the manifest constant flag, but otherwise just ignores it and indeed treats it the same as an auto return value.
So nothing special, arguably just the parser not throwing an error when it perhaps could.