help me to understadn increment ?

[espace]

hi,

i don't understand the principle of increment with javascript. This snippet works well :

//in update
f.big=(obj,speed)=>{
	if (obj.scale.x < 8) {
		obj.scale.setTo(obj.scale.x + speed)
	}
}

but this example don't work however it's supposed to be the same...why that don't works ?

// in update
f.pointer_big=(obj,speed)=>{
	if (obj.scale.x < 8) {
		obj.scale.setTo(obj.scale.x++ * speed)
	}
}

 

[tips4design]

What are you trying to do in the second case? What is target value?

[espace]

i would the same than the one case.

[mattstyles]

Your 2 examples aren't the same, and I can't see why you'd think they would be comparable. I can see why you'd be confused by the output of the 2nd though, but if you are confused by the output then its to do with the order of operations.

Postfix operators (generally) have lower precedence so they happen after other operands, prefix operators (generally) are executed before.

i.e.

var x = 10

x++ + 2
=> 10 + 2 => change x
// 12, x === 11

x = 10

++x + 2
=> change x => 11 + 2
// 13, x === 11

I'm not sure on the exact order of operands in JS, but I'd pretty much expect prefix to happen first and postfix to happen last in most expressions.