Question

I have a for loop which iterates through all items:

for (i=0; i < this.widgets.length; i++) {
  this.changeWidgetArray(this.widgets[i]); 
}

In the for loop, for every single element, I call “changeWidgetArray”.
In this method, the “widgets”-Array from above is changed.
Does this array-changing in “changeWidgetArray” affect the loop iteration?

My question is:

In the moment, when the iteration begins with the first item, is the whole array with all of its elements “collected”, or does JavaScript dynamically fetch one by one before the next iteration step begins.

Or does this depend on the JavaScript implementation? Is this defined in the ECMA-Script specification?

Thanks alot in advance

Answer 1

YES:

for (i=0; i < this.widgets.length; i++) {
  this.changeWidgetArray(); 
}

NO:

for (var i=0, max=this.widgets.length; i < max; i++) {
  this.changeWidgetArray(); 
}