how to return to top of for loop in javascript

Question

Maybe this is a dumb question but is there a way to return to the top of a loop?

Example:

for(var i = 0; i < 5; i++) {
 if(i == 3)
 return;
 alert(i);
}

What you'd expect in other languages is that the alert would trigger 4 times like so:

alert(0); alert(1); alert(2); alert(4);

but instead, the function is exited immediately when i is 3. What gives?

• Jakub Konecki: Could you give an example of 'other languages'?
• Chuck: What languages are you thinking of where returning in the middle of a loop makes the loop continue? It's not so in any language I know.
• JeremyDWill: C# does not continue the loop - once you execute the 'return' statement, the function exits immediately, just as it does in javascript. C# also uses the 'continue' statement for the execution flow you are trying to accomplish.

Answer 1

Use continue instead of return.

Example: http://jsfiddle.net/TYLgJ/

for(var i = 0; i < 5; i++) {
 if(i == 3)
 continue;
 alert(i);
}

If you wanted to completely halt the loop at that point, you would use break instead of return. The return statement is used to return a value from a function that is being executed.

EDIT: Documentation links provided by @epascarello the comments below.

• Docs for continue: https://developer.mozilla.org/en/JavaScript/Reference/Statements/continue
• Docs for return: https://developer.mozilla.org/en/JavaScript/Reference/Statements/return

• epascarello: continue: developer.mozilla.org/en/JavaScript/Reference/Statements/… return: developer.mozilla.org/en/JavaScript/Reference/Statements/return
• user113716: @epascarello - Thanks for adding the references. :o)
• user113716: I guess mine was down-voted too. Down-voters should give a reason.

Answer 2

For what it's worth, you can also label them:

OUTER_LOOP: for (var o = 0; o < 3; o++) {
 INNER_LOOP: for (var i = 0; i < 3; i++) {
 if (o && i) {
 continue OUTER_LOOP;
 }
 console.info(o, ':', i);
 }
}

outputs:

0 : 0
0 : 1
0 : 2
1 : 0
2 : 0