JavaScript; parsing an IF statement with OR clauses

My question is qu开发者_StackOverflow中文版ite simple, if I declare an IF statement with a series of OR clauses will JavaScript read all of the ORs or stop at the first one that is satisfied?

Thanks in advance.

Stops at the first one. It's called short-circuiting

http://en.wikipedia.org/wiki/Short-circuit_evaluation https://developer.mozilla.org/en/JavaScript/Reference/Operators/Logical_Operators

It should only process upto the first OR that returns true:

if (a || b || c) { 

}

If a is false, b is true and c is true, it will process upto b.

function foo() {
    return true;
}

function bar() {
    alert("bar");
}

foo() || bar(); // true - no alert
bar() || foo(); // true - alert of "bar"

If the first condition is satisfied, other conditions of or are not evaluated