w

1 files changed, 13 insertions, 4 deletions

diff --git a/compat/borrowed-ptr-fwd.hpp b/compat/borrowed-ptr-fwd.hpp
index 38927cc6..5f9c09f4 100644
--- a/compat/borrowed-ptr-fwd.hpp
+++ b/compat/borrowed-ptr-fwd.hpp
@@ -1,10 +1,19 @@
 #pragma once
+
 namespace floormat {
 
 struct bptr_base;
-template<typename T> class bptr;
-template<typename To, typename From> bptr<To> static_pointer_cast(const bptr<From>& p) noexcept;
-template<typename T> bptr(T* ptr) -> bptr<T>;
-template<typename T> bptr(const T* ptr) -> bptr<const T>;
+
+template<typename T>
+requires std::is_convertible_v<T*, const bptr_base*>
+class bptr;
+
+template<typename T>
+requires std::is_convertible_v<T*, const bptr_base*>
+bptr(T* ptr) -> bptr<T>;
+
+template<typename T>
+requires std::is_convertible_v<T*, const bptr_base*>
+bptr(const T* ptr) -> bptr<const T>;
 
 } // namespace floormat