Feature or bug: implicit cast from false to 0

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Observe this code (VC7.1):

void Test(const char*)
{
}

int main(void)
{
Test( false ); // OK
Test( true ); // error C2664: cannot convert from bool to const char*
}

Shouldn't the first call also produce the compiler error?

 

[Bo Persson]

Observe this code (VC7.1):

void Test(const char*)
{
}

int main(void)
{
Test( false ); // OK
Test( true ); // error C2664: cannot convert from bool to const
char*
}

Shouldn't the first call also produce the compiler error?

No - false, 0, NULL, 1 - 1, etc are all examples of constant integral
expressions, that can be used as the null pointer value.


Test(false) works just as well as Test(0) or Test(NULL).


Bo Persson