How to replace conditional operator by && and ||?

Question

I'm working on Expression parser and I would like add conditional operator (?:) I've changeed && and || to act like the onces in javascript, using this code:

case '&&':
    $stack->push($op1 && $op2 ? $op2 : ($op1 ? $op2 : $op1)); break;
case '||':
    $stack->push($op1 ? $op1 : $op2); break;

so I thought that I just replace foo ? bar : baz by foo && bar || baz is it possible using regex? if operators can be nested, each argument to conditional operator can have same operator.

Answer 1

foo && bar || baz and foo ? bar : baz are not equivalent.

Suppose both foo is a value considered to be true and bar is a value considered to be false. In that case, foo && bar is false, so the value of the first expression is baz. The ternary operator (?:), on the other hand, alwys returns the second argument when the first argunent is true, so it will return bar.

Try 1 && 0 || 2 and 1 ? 0 : 2. The first is 2 and the second 0.

The simplest way to evaluate the ternary operator is as a single operator taking three operands

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By the way, op1 && op2 could be written much more simply as op1 ? op2 : op1.