OriginalType

enum E : real { a = 0 } // NOTE: explicit initialization to 0 required during Enum init deprecation cycle
enum F : E    { a = E.a }
alias G = const(F);
static assert(is(OriginalType!E == real));
static assert(is(OriginalType!F == real));
static assert(is(OriginalType!G == const real));