refactor: move is_func to own type traits file

1 files changed, 16 insertions, 0 deletions

diff --git a/src/DI/type_traits.hpp b/src/DI/type_traits.hpp
new file mode 100644
index 0000000..a852a4f
--- /dev/null
+++ b/src/DI/type_traits.hpp
@@ -0,0 +1,16 @@
+#pragma once
+
+#include <functional>
+
+template <typename NotAFunc>
+struct is_func : public std::false_type // NOLINT(readability-identifier-naming)
+{
+};
+
+template <typename Return, typename... Args>
+struct is_func<std::function<Return(Args...)>> : public std::true_type
+{
+};
+
+template <typename PossiblyFunc>
+inline constexpr bool is_func_v = is_func<PossiblyFunc>::value;