Polymorphic Allocator

Polymorphic Allocator

To be concise, a polymorphic allocator conforms to the rules of an allocator from the Standard Library.

However, at its core, it uses a memory resource object to perform memory management.

Polymorphic Allocator contains a pointer to a memory resource class, and that’s why it can use a virtual method dispatch. You can change the memory resource at runtime while keeping the type of the allocator.

All the types for polymorphic allocators live in a separate namespace std::pmr (PMR stands for Polymorphic Memory Resource), in the <memory_resource> header.

Core elements of pmr:

• std::pmr::memory_resource - is an abstract base class for all other implementations. It defines the following pure virtual methods:

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