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+---- Thread: Rule 7.0.2: operator const char *() (/showthread.php?tid=1710)
Rule 7.0.2: operator const char *() - karos - 11-10-2024
Hello,
Rule 7.0.2 has an exception for converting pointer to bool, and requires an explicit operator bool() for classes. But what if a class, let's say a wrapper class for strings, provides an operator const char *? Consider the following example:
Code:
class C
{
public:
operator const char *() const;
};
void f(C c)
{
if (c); // C is converted twice: C -> const char * -> bool
}Shall the commented line be considered compliant with this rule (because each of the conversion steps by itself is compliant), or not (because as a whole it is the conversion of a class to bool without using an explicit operator bool)?
RE: Rule 7.0.2: operator const char *() - misra cpp - 11-10-2024
The later, it should be treated as non-compliant. In effect you've got an object of type C being converted to bool, even if it does go through extra steps.
if (c.operator()) ;
or
if ( c ); // if C declared operator bool();
would both be compliant.
RE: Rule 7.0.2: operator const char *() - karos - 14-10-2024
Alright, thank you very much for the clarification.