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C++ Language/Indirection/TypedNull

< C++ Language | Indirection
C++ Language
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  6. Indirection
    1. Pointers
    2. Typed NULL
    3. Arrays
    4. Reference Variables
    5. Rvalue-References
    6. Smart Pointers
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  13. Obsolete Features

The traditional NULL macro was really just a int with value 0. This is commonly used as a special value assigned to a pointer variable, having the semantic meaning of "not pointing at anything" (because computers will never try to use their memory at address 0).

Modern C++ uses nullptr instead of NULL, because nullptr has a dedicated std::nullptr_t type.

Additional information about nullptr

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