Alexander Nasonov writes:
Good news, I can use mpl:find_if even though typeof isn't available!
This is how I do it:
1. define overload_set_iter class template that takes an overload set and an iterator for current position. (If it was ever possible, deref could return a signature of an overload the iterator refers to).
What if you define a "signature" as an (overload set, index) pair, declare it as a standard way to pass things around (within your library, that is), and make 'overload_set_iter' return that on dereference? Any reason why the approach you outline below is preferable?
2. specialize mpl::aux::iter_apply1 for overload_set_iter. Unlike primary template, specialized version doesn't deref overload_set_iter, it dereferences nested position iterator and then pass that position to test1 metafunction. This metafunction tests a predicate passed to iter_apply1 indirectly (that is, by position).
This only one local hack I'm able to use mpl::find_if. This is much better then before.
Aleksey, if you're interested in tighter integration between mpl and overloads,
Definitely.
let me use more hacks legally. I'm not sure it will always be possible not to touch mpl code, but I'll try.
I'm willing to make the necessary changes once we explore the design space to the extent that would make the need obvious.
PS. I'll check my e-mail tomorrow morning and then I'll check it again only on Tuesday because I'm on vacation.
Sure thing. Have fun, -- Aleksey Gurtovoy MetaCommunications Engineering