1.

pragma(msg, is(i == enum) || is(typeof(i) == enum)); // <- false?!

I can't find a way to identify that i is an enum, not a variable; can not be assigned, has no address, etc.

2.

import std.stdio;

pragma(msg, !is(std) && is(typeof(std))); // <- true?!

std.stdio is a module, it looks like a variable. typeof(std) == void... What the? Why does it even have a type?

I can't find a sensible way to distinguish std from any other regular variable.