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(C++) new

C++ keyword to dynamically allocate memory and returning a pointer to this memory location. If the allocation of memory fails, std::bad_alloc is thrown and a pointer to null is returned.

When the pointer is no longer needed, delete must be called.

Examples

• new example 1: naked new and delete (note [4,5])
• new example 2: new and a smart pointer

Advice

• Avoid 'naked' new and delete [4,5]
• Prefer the use of smart pointers over the use of plain pointers [1-3].

• Use smart pointers to avoid forgetting to delete objects created using new [6]

References

1. Scott Meyers. Effective C++ (3rd edition). ISBN: 0-321-33487-6. Item 13: 'Use objects to manage resources'.
2. Scott Meyers. Effective C++ (3rd edition). ISBN: 0-321-33487-6. Item 17: 'Store newed objects in smart pointers in standalone statements'
3. Herb Sutter, Andrei Alexandrescu. C++ coding standards: 101 rules, guidelines, and best practices. 2005. ISBN: 0-32-111358-6. Chapter 13: 'Ensure resources are owned by objects. Use explicit RAII and smart pointers.
4. Bjarne Stroustrup. The C++ Programming Language (4th edition). 2013. ISBN: 978-0-321-56384-2. Page 19, 1.3.2 'Advice', item 3: 'Avoid 'naked' new and delete'
5. Bjarne Stroustrup. The C++ Programming Language (4th edition). 2013. ISBN: 978-0-321-56384-2. Chapter 11.6. Advice. page 303: '[4] Avoid "naked new" and "naked delete"'
6. Bjarne Stroustrup. The C++ Programming Language (4th edition). 2013. ISBN: 978-0-321-56384-2. Chapter 21.4. Advice. page 640: '[1] Use unique_ptr or shared_ptr to avoid forgetting to delete objects created using new'

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