unique_ptr, the ultimate wrapper

I just started this C++ version of a concept I've been working on for over a year now (more about that in future posts). In the process of doing the groundwork, I started doing my usual thing : write wrappers around libs, to handle a few things for me, primarily making sure that resources are freed when they aren't used any more. So, here I am, mechanically writing a wrapper for libCurl's easy handle, constructor, destructor, rule of five, something I feel like I've done a million times ; and then I remembered something...

A little while ago, I found a really useful talk about coroutines, where the speaker does a really neat use of std::unique_ptr, painlessly managing the lifetime of the coroutine_handle. It should work here too and look something like:

std::unique_ptr<CURL,curl_easy_cleanup> CurlHandle;

Something funny happened when I tried: as soon as I had typed ...<CURL, , CoPilot suggested that esoteric part that converts the function pointer into a type : decltype(&curl_easy_cleanup) ! This did help me figure out the syntax but, more importantly, it made me realize this was far from a new idea since the IA could parrot it out.

Before this, I thought unique_ptr was only some new-replacement that improved memory allocations management. Before watching this talk, I wasn't aware it had an optional Deleter template parameter. I should have known better as C++ has pretty much always encouraged us not to consider memory as any specific sort of resource. I now see unique_ptr as a universal wrapper for a lot of libraries with C interfaces, it makes it dead easy to safely keep a handle to something, and be sure cleanup will happen properly whatever the code does and however exceptions fire.

I'm so happy with this discovery, I thought I should share it, hoping it will help somebody else (even if I have figured out I am late to the party and many will go "What? Ya didn't know ?")

(continue to follow-up post...)