On Friday, 2 May 2014 at 12:45:44 UTC, Nordlöw wrote:
I'd be verbose. It's an uncommon operation, bound to surprise
a reader
a bit.It's better to type a few more letters.
See update.
I did not try to compile it, but what happens if the enum
elements
have the same name ? The same min/max/values ?
Like this:
enum E1 { a, b, c }
alias E111 = join!(E1, E1, E1);
This should give a better error message, than current mixin
error.
I'll work on that.
I would put it in std.typecons, since it's a type constructor
Ok.
Thx!
Here's my try at detecting member names collision at compile time:
template MemberNamesUnion(E...) if (allSatisfy!(isEnum, E))
{
bool[string] allMembers; // used to detect member collisions
mixin({
string r = "enum MemberNamesUnion { ";
foreach (T; E) {
import std.range: join;
foreach (member; __traits(allMembers, T)) {
static assert (member in allMembers, "Member
collision");
allMembers[member] = true;
}
r ~= [__traits(allMembers, T)].join(",") ~ ",";
}
return r ~ " }";
}());
}
It fails as
enums.d(25,46): Error: static variable allMembers cannot be read
at compile time
enums.d(25,21): while evaluating: static assert("a" in
allMembers)
Is there a solution to this problem?
