Can (a==1)&&(a==2)&&(a==3) evaluate to true? (and can it be useful?)

Question

Inspired by another question regarding java-script language. Can the expression

 (a==1)&&(a==2)&&(a==3)

evaluate to true i

Answer 1

Other things not mentioned yet (source):

• a might have overloaded operator int(), the operator for implicit conversion to int (instead of operator== as covered by other answers).
• a might be a preprocessor macro.

Example of the latter:

int b = 0;
#define a ++b
if ((a==1)&&(a==2)&&(a==3))
    std::cout << "aha\n";