Compiler error for conditional operator “?:” when used with typecasting operator

Question

Following code is in simplest form:

struct X {
  operator char () const { return \'a\'; }
};

int main ()
{
  X obj, *p = &obj;
  char a = *p;  // ok
  char          


        

Answer 1

The error is correct. operands to ?: have different types: ‘X’ the first, and ‘char’ the second. The compiler cannot know that you want the expression to be a char in the end - that will happen later, after the evaluation of the whole expression (true)? *p : 'z'; - an evaluation which cannot be done in the first place due to type discrepancies.