See if you can guess what this will output:
function allNames() {
var names = [ 'dan', 'anthony', 'pavel' ];
for (name in names) {
console.log(name);
}
}
allNames();
If you guessed this:
0
1
2
...then you are right! Congratulations!
What you might not have guessed, is what this will output:
console.log(window.name);
it's:
"2"
Iteration is assignment, and without the use of the var keyword, you're really using the global object - which in this context is the window object.
So the original function is equivalent to:
function allNames() {
var names = [ 'dan', 'anthony', 'pavel' ];
for (window.name in names) {
console.log(name);
}
}
By @danlash