Why Is std::make_unique Preferred Over the New Operator for Creating std::unique_ptr Objects?

Why Use std::make_unique Over the New Operator for Allocating std::unique_ptr?

When creating a std::unique_ptr object, it is recommended to use std::make_unique instead of the new operator. Here are the main advantages of using std::make_unique:

Improved Syntax

std::make_unique simplifies the initialization syntax, requiring the type of the object to be mentioned only once. This makes the code more concise and less prone to typos.

Convenience and Encapsulation

std::make_unique encapsulates the allocation and initialization process, making it more convenient and error-prone. It manages the memory allocation and assignment to the std::unique_ptr in a single step.

Exception Safety

std::make_unique is exception-safe, meaning it can gracefully handle exceptions that may occur during object allocation. If an exception is thrown during allocation, std::make_unique ensures that the allocated memory is correctly cleaned up, preventing memory leaks.

Avoidance of Unspecified Evaluation Order

Using std::make_unique helps avoid unspecified evaluation order issues. The evaluation order of expressions involving new and unique_ptr can be problematic, potentially leading to memory leaks. std::make_unique ensures that the object is correctly allocated and assigned to the unique_ptr before any other operations are performed.

Disadvantages:

• Custom Deleters: std::make_unique cannot be used if you need to use a custom deleter for your unique_ptr object.
• Adopting Raw Pointers: If you are adopting a raw pointer from another source, you cannot use std::make_unique directly.

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