Matt Diephouse (via RT) wrote:
There's no real way to set a vtable function at runtime. It's
possible to use the PIR compiler to eval a new function, but there's
no way to take an existing sub and add it as a vtable function[1].
Before :vtable, this operation simply meant adding the sub to the new
namespace under the right name. But since that's going away, we need
a new way to do things.
I suspect we need some sort of set_vtable opcode.
set_vtable ['Foo'; 'Bar'], 'get_string', $P0
Maybe there should be set_root_vtable and set_hll_vtable variants to
go along with to match the set_*global opcodes.
For classes, the 'add_method' method takes a named parameter to say
whether it's a vtable function. And, vtable functions aren't stored in
the namespace at all anymore, but in a data structure inside the class,
so you wouldn't have 'root' and 'hll' variants. I can see potentially
see adding an 'add_vtable' vtable function, parallel to add_method,
add_attribute, etc.
What's the use case for modifying a low-level PMC's vtable entries at
runtime? Or, are you only talking about overriding vtable functions in a
class?
Allison
