On 8/21/2011 3:55 AM, Jacob Carlborg wrote:
What are the chances of D getting proper runtime reflection? Something
like this:
class Foo
{
private int a;
private void bar (int i)
{
a = i;
}
}
auto foo = new Foo;
Object o = foo;
o.setInstanceVariable("a", 3);
assert(foo.a == 3);
This would be useful as well:
o.send("bar", 5);
assert(foo.a == 5);
assert(foo.a == o.getInstanceVariable("a"));
Currently I have most use of the first example. These example should
work regardless if the fields/methods are private, protected or public.
As far as I know this wouldn't require any changes to the language,
only the compiler and runtime would need to be modified. To me, it
doesn't look that complicated to implement, the runtime just needs to
store an associative arrays that maps names of instance variables and
methods to their addresses. This could probably be stored in the
ClassInfo. Something like this:
Foo.classinfo.setInstanceVariable(foo, "a", 3);
And this could be shorted to:
o.setInstanceVariable("a", 3);
"setInstanceVariable" could just forward the call to the class info.
It's not /quite/ the same thing as you're asking, but I'm facing a
problem that seems to fundamentally prevent dynamic typing to work
correctly (which is related, but of course not the same thing as,
reflection):
http://stackoverflow.com/questions/7102648/using-dynamic-typing-in-d-a-statically-typed-language
As much as I'd love to see it happen, I can't see how templates and
reflection would actually work at run-time.
