Look for an Exit

It is always good to have an exit strategy. You know when you are at a party and you are stuck talking to that one relative that has to go into every gory detail concerning their ailments? If that has not happened to you, then most likely you are that relative, but I digress. In loops, it is good to have an exit strategy.

Imagine you have a loop that is running and looping over a large array. Perhaps you do not need to go over the entire array, but simply need to loop over it until some sort of logical condition in your program is met. Why waste processing power, time, etc. finishing the loop when you can exit and get on with bigger and better things. This is where exiting the loop comes in handy.

I have seen this before…

for ( i = 0; i <= myArray.length; i++ ) {
    doSomething();
    if(this === that){
        i = myArray.length + 1;
    }
}

See the line that is -> i = myArray.length + 1; ? That is a hacky (if not tacky) way to exit. It is prone to being buggy and not a standard way to do it. Would it would? Probably, but why settle?

There is a better way…

for ( i = 0; i <= myArray.length; i++ ) {
    doSomething();
    if(this === that){
        break;
    }
}

The break keyword can be used to break out of a loop and stop the loop from finishing its processing.

What if you want to stop the loop from processing and tell your code to skip a step and keep going? There is a keyword for that also…continue; Continue forces the loop to jump to the next cycle.

Happy Coding!

Clay Hess