Question

If an expression evaluates multiple && operators, and does not evaluate any operators of lower precedence (eg. ||, ?:), will the expression evaluate to 0 as soon as one of the &&s return 0, or will it finish evaluating the remaining &&s?

For example,

q=0; w=1; e=1; r=1;
if(q && w && r && e) {}

Will this if() evaluate to false as soon as q && w evaluates to 0 (since the remaining && must all evaluate to 0 regardless of the right hand operators)?

Answer 1

Yes, evaluation will terminate early (“short circuit”) as soon as a false expression is encountered. There is one exception to this: if the && operator has been overloaded for the relevant types of arguments. This is strongly discouraged and extremely rare, but could happen.