On Sunday, 30 April 2017 at 20:58:36 UTC, jkpl wrote:
On Sunday, 30 April 2017 at 20:05:59 UTC, Kevin Balbas wrote:
I've got the following code snippet, which almost does what I
want.
struct TaggedType {}
@TaggedType
struct Foo {}
@TaggedType
struct Bar {}
string GenerateTypeEnum()
{
string enumString = "enum TypeEnum {";
foreach (name; __traits(allMembers, mixin(__MODULE__)))
{
import std.traits;
static if (hasUDA!(mixin(name), TaggedType))
{
enumString ~= name;
enumString ~= "Type,";
}
}
enumString ~= "}";
return enumString;
}
// generates enum TypeEnum {FooType,BarType,}
mixin(GenerateTypeEnum());
This works great, except that TypeEnum isn't accessible from
other modules (undefined identifier 'TypeEnum'), which is kind
of the point of doing this (I'm using the enum as a
system-wide tag for inter-thread communication). I can
imagine why this would be the case, but it's a pretty serious
problem. Is there a way to do this?
if i put your sniped in b.d and import in a.d b then i'm able
to access TypeEnum.
You r problem must be something stupid that's not related to
UDA/mixins.
That leads to this question (sorry) but at least do you import
the module that contains TypeEnum ?
Yes, and in fact, if I manually comment out the code (in my
actual program, not the test program) in the same module and
replace it with a hard-coded enum, the other code can access it
perfectly. I wouldn't be surprised if it was something stupid,
but I'm not even sure what could go wrong between those two
cases. I figured it was some kind of ordering thing, but I
honestly have no idea.
Strangely enough, it does work fine in the test snippet, so I'm
trying to figure out what could be going on since I literally
copied the function verbatim from my test program to my main one.
Now that I've realized this I'm working on how to repro it in
the smaller program.
