On Thu, 03 May 2012 14:05:26 -0400, Mehrdad <[email protected]> wrote:
There's the RTInfo method I told you about (recently added) if you want
to stick the information directly into TypeInfo at compile time.
There's also static ctors. Just add a hashtable based on the class
name, and use typeid(this).name as the initial key. You have to handle
all the inheritance of properties yourself, but that shouldn't be too
difficult.
-Steve
Ooh... how do I get RTInfo? It's not in druntime/phobos....
https://github.com/D-Programming-Language/druntime/blob/master/import/object.di#L622
Need the github versions of dmd/druntime/phobos.
Basically how it works is the compiler evaluates RTInfo!T where T is the
type for which TypeInfo is being generated, and places the result into a
location that is returned by TypeInfo.rtInfo property. This all happens
at compile-time, so it effectively gives you a hook to store runtime type
information into the TypeInfo.
As far as I know, there's not official documentation on it, it's a pretty
beta feature. But I think it will open a door to actual runtime type
information that we never had before.
One limitation is, it has to be inside the runtime, and specifically in
object.di. However, we may be able to effectively generate class/struct
specific runtime type information. For example:
struct RTTI
{
// druntime-specified properties
...
// type-specific properties
void *typeSpecificProperties;
}
template RTInfo_Instance(T)
{
static if(is(typeof({void *x = T.__rtInfo();}))
immutable RTTI RTInfo_Instance = RTTI(..., T.__rtInfo());
else
immutable RTTI RTInfo_Instance = RTTI(..., null);
}
template RTInfo(T)
{
immutable void * RTInfo = &RTInfo_Instance!T;
}
I have no idea if this works :) But I'm *positive* someone with better
template skills than me can make something like this work.
-Steve
