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Full Version: Rationale for 11.9 -- NULL constant
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Can anyone explain what the rationale is for this rule? I could think of several arguments for why you shouldn't use NULL, and should prefer a plain 0 (as is generally preferred in C++). This feels like a stylistic issue.

The standard (ISO 9899:1999 defines a null pointer constant:

Quote:An integral constant expression with the value 0 , or such an expression cast to type void *, is called a null pointer constant.
This means, for example that it is legitimate in the C language to compare a pointer expression with any form of integer constant expression including for example '\0' or any enum constant of value 0. For this reason it is advisable to use NULL wherever a null pointer constant is intended.

The semantics are subtly different in C++