How to check if args[1] is in a range of numbers

Solution 1:

Unlike Python, you cannot do 2 comparisons in the same "block" of code.

The code 1 < 2 < 3 is actually doing (1 < 2) < 3 which actually works out as true < 3 and as JS uses false=0, true=1, you are now checking if 1 < 3, not if 2 is.

So, in your case, it will always return true as either false(0) OR true(1) will be less than 10.

Just change it to -10 < parseInt(args[1]) && parseInt(args[1]) < 10 with an undefined/length check before it.

For example:

if (args.length >= 2 && -10 < parseInt(args[1]) && parseInt(args[1]) < 10) {
    message.channel.send("yes");
} else {
    message.channel.send("no");
}

Solution 2:

JS won't throw any error of IndexOutOfRange as other languages like C#, Java.

It'll return undefined instead.

Please below snippet for how it may happen.

If your logic is to check a value in between -10 and 10, you have to change a little bit with an & operator.

Cheers.