proxiable_targettemplate <class T, class F>
concept proxiable_target = proxiable<observer-ptr<T>, F>;
See make_proxy_view for the definition of the exposition-only class template observer-ptr.
#include "proxy.h"
struct Runnable : pro::facade_builder
::add_convention<pro::operator_dispatch<"()">, void()>
::build {};
int main() {
auto fun = [] {};
static_assert(pro::proxiable_target<decltype(fun), Runnable>);
static_assert(!pro::proxiable_target<int, Runnable>);
}