Multiple comparison operators in a JavaScript boolean expression

Question

I'm trying to check whether the variable y is less than x and greater than z, but this boolean expression is returning false for some reason. Does JavaScript allow boolean expressions to be written concisely like this? If so, what is the correct syntax?

x = 2;
y = 3;
z = 4;

if(x > y > z){
    alert("x > y > z"); //Nothing happens!
}

Answer 1

Change your test to

if (x > y && y > z){

When you write (x > y > z), this is equivalent to ((x>y)>z), so you're comparing a boolean (x>y) to z. In this test, true is converted to 1, which isn't greater than 2.

Answer 2

You want

if(x > y && y > z){
    alert("x > y > z"); //Nothing happens!
}

Javascript will try to parse your original statement from left to right and you'll end up comparing z to a boolean value which will then be parsed to a number (0 or 1).

So your original statement is equivalent to

if( (x > y && 1 > z) || (x <= y && 0 > z))