In C++, there are eleven keywords which are simply alternate spellings of operators normally written with punctuation. These keywords are treated as such even in the preprocessor. They function as operators in ‘#if’, and they cannot be defined as macros or poisoned. In C, you can request that those keywords take their C++ meaning by including iso646.h. That header defines each one as a normal object-like macro expanding to the appropriate punctuator.
These are the named operators and their corresponding punctuators:
| Named Operator | Punctuator |
and | && |
and_eq | &= |
bitand | & |
bitor | | |
compl | ~ |
not | ! |
not_eq | != |
or | || |
or_eq | |= |
xor | ^ |
xor_eq | ^= |