On Sunday, 17 March 2013 at 14:27:32 UTC, simendsjo wrote:
On Sunday, 17 March 2013 at 13:30:29 UTC, Maxim Fomin wrote:
On Sunday, 17 March 2013 at 12:16:08 UTC, simendsjo wrote:
When a struct contains methods, __traits(allMembers reports a
member called "this". What is "this"?
void main() {
struct S { int i; }
struct A { int i; void f() {} }
pragma(msg, __traits(allMembers, S)); // i
pragma(msg, __traits(allMembers, A)); // i, f, this
}
This is context pointer. Move outside of function to not to
have it.
Should it be included? The documentation is a bit sparse:
http://dlang.org/traits.html#allMembers, but every member
listed there are methods in the class or from Object. No hidden
this or vtbl shows in the example.
Yes, it should be documented explicitly. I think it should be
included because there is actually a special member which has
runtime storage and listing "this" does not make much harm,
indeed it can be useful (probably some phobos code depend on
this). Vtbl can be accessed anyway and class is reference type,
so comparing allMembers for structs and classes is not very good.
