C++26: More function wrappers
The C++26 standard is slated to include new function wrappers, notably `std::copyable_function`, as detailed in an article published on May 20, 2026, on Lobsters via sandordargo.com. This upcoming feature aims to provide a standard library solution for wrapping callable objects that can be copied, addressing a long-standing limitation present in `std::function`, which typically requires wrapped callables to be move-only or have specific copy semantics. The introduction of `std::copyable_function` is expected to simplify the design and implementation of systems where function objects need to be stored in containers, passed across thread boundaries, or otherwise duplicated without complex manual memory management or custom wrapper types. This enhancement directly supports patterns such as observer systems, command queues, and parallel algorithms where the ability to duplicate a callable object is crucial for correct and efficient operation. This addition aligns with the ongoing evolution of the C++ standard library to offer more expressive and safer mechanisms for common programming paradigms. By standardizing a copyable function wrapper, developers can expect improved interoperability and reduced boilerplate when working with callbacks, event handlers, and other scenarios where function objects' lifetimes and ownership need careful management. The move towards `std::copyable_function` reflects a broader effort within the C++ committee to enhance the language's capabilities for modern, concurrent, and high-performance applications. It provides a type-erased wrapper that can hold any copyable callable, offering a more convenient and safer alternative to raw function pointers or custom polymorphic wrappers, thereby making it easier to write robust and maintainable code for complex systems.
Developers gain a standard, safer way to handle copyable callable objects, simplifying concurrent programming and callback designs by reducing the need for custom solutions.