renaming can_invoke to is_invokable

example/is_invokable_constexpr_member_function_pointer.cpp

@@ -0,0 +1,41 @@
+/*!<-
+Copyright (c) 2016 Barrett Adair
+
+Distributed under the Boost Software License, Version 1.0.
+(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
+->*/
+
+#include <callable_traits/config.hpp>
+#ifdef CALLABLE_TRAITS_DISABLE_CONSTEXPR_CHECKS
+int main(){ return 0; }
+#else
+
+//[ is_invokable_constexpr_member_function_pointer
+#include <type_traits>
+#include <callable_traits/is_invokable_constexpr.hpp>
+
+// NOTE: Due to non-compliance in MSVC, is_invokable_constexpr
+// always returns std::false_type on that compiler, which
+// causes a static assert below to fail.
+
+namespace ct = callable_traits;
+
+struct foo {
+    constexpr int bar(int) const {
+        return 1;
+    }
+};
+
+using pmf_constant = std::integral_constant<decltype(&foo::bar), &foo::bar>;
+
+// is_invokable_constexpr returns true here because foo::bar
+// is constexpr, and the arguments are valid to INVOKE
+static_assert(ct::is_invokable_constexpr(pmf_constant{}, foo{}, 0), "");
+
+// is_invokable_constexpr returns false here because even though
+// foo::bar is constexpr, the arguments do not obey INVOKE rules
+static_assert(!ct::is_invokable_constexpr(pmf_constant{}, foo{}), "");
+
+int main() {}
+//]
+#endif