[codethinki]

cth::reconstruct_at(object, std::move(other)) destroys object and move constructs it from other in place. It is a move assignment for types where = default is wrong, e.g. types that own a resource through cth::move_ptr, whose move assignment overwrites without destroying:

Device& operator=(Device&& other) noexcept { return cth::reconstruct_at(*this, std::move(other)); }

• noexcept: requires a nothrow move constructor and destructor, a throw after the destruction would leave a dead object
• rejects polymorphic types, std::destroy_at would run the most derived destructor
• self assignment is a no op
• preconditions (not checkable): object is not a base class subobject or [[no_unique_address]] member, and does not own other

cth_engine uses it for its Vulkan handle classes.

[codethinki]

Not merging: move assignment through destroy + reconstruct in place is UB on base class subobjects, too easy to misuse. cth_engine uses std::unique_ptr with a deleter that holds the destroy context instead.