How to 'continue' inside a each loop : underscore, node.js

Question

The code in node.js is simple enough.

_.each(users, function(u, index) {
  if (u.superUser === false) {
    //return false would break
    //continue?
  }
  //Some code
});

My question is how can I continue to next index without executing "Some code" if superUser is set to false?

PS: I know an else condition would solve the problem. Still curious to know the answer.

Peter Lyons · Accepted Answer · 2016-06-22T14:03:03.750

139

_.each(users, function(u, index) {
  if (u.superUser === false) {
    return;
    //this does not break. _.each will always run
    //the iterator function for the entire array
    //return value from the iterator is ignored
  }
  //Some code
});

Side note that with lodash (not underscore) _.forEach if you DO want to end the "loop" early you can explicitly return false from the iteratee function and lodash will terminate the forEach loop early.

edited Jun 22 '16 at 14:03

answered Sep 06 '13 at 06:17

Peter Lyons

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Why is this not applicable? https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/continue – Con Antonakos Feb 03 '15 at 17:58
6

Because `_.each` and a regular `for () {}` loop are not the same thing. – Peter Lyons Feb 03 '15 at 18:19
@ConAntonakos When you use `for-each(collection, callback)` in JS there isn't any for loop inside `callback` hence `break/continue` do not apply. – pgpb.padilla Nov 28 '15 at 19:33

score 12 · Answer 2 · answered Nov 28 '15 at 18:35

12

Instead of continue statement in for loop you can use return statement in _.each() in underscore.js it will skip the current iteration only.

answered Nov 28 '15 at 18:35

Vishnu PS

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score 0 · Answer 3 · answered Sep 06 '13 at 06:16

0

_.each(users, function(u, index) {
  if (u.superUser) {
    //Some code
  }
});

answered Sep 06 '13 at 06:16

pdoherty926

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Sorry. I should have put scenario in detail. I need to execute some code if super user is false and then continue. There will be another condition say, if (superUser != false && activated) for which I need to do something else and execute "Some code" and then there's else for which I need to execute "Some code". I just wanted to know if there's a way to do it without rewriting same code inside both else if and else. I do not want to create another function for this. – Sep 06 '13 at 06:23
1

He was asking how to avoid that very poor practice of arrow-code. – David Betz Dec 24 '13 at 02:08

How to 'continue' inside a each loop : underscore, node.js

3 Answers3