Info

How much does returning a value slow a function down?

Preparation code

<script>
  function noReturn(err, callback) {
    if (err) {
      callback('error');
    } else {
      callback(null, 'value');
    }
  }
  
  function doesReturn(err, callback) {
    if (err) {
      return callback('error');
    }

    return callback(null, 'value');
  }

  function doesValuelessReturn(err, callback) {
    if (err) {
      callback('error');
    } else {
      callback(null, 'value');
      return;
    }
  }
</script>

Test runner

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Java applet disabled.

noReturn(null, function(err, result) {
});

doesReturn(null, function(err, result) {
});

doesValuelessReturn(null, function(err, result) {
});

noReturn('err', function(err, result) {
});

doesReturn('err', function(err, result) {
});

doesValuelessReturn('err', function(err, result) {
});

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Revisions

You can edit these tests or add even more tests to this page by appending /edit to the URL. Here’s a list of current revisions for this page:

• Revision 1: published by Alexis Deveria on 17th September 2010
• Revision 3: published on 14th April 2012
• Revision 4: published on 19th December 2012
• Revision 5: published on 19th December 2012
• Revision 6: published by max jooher on 19th December 2012
• Revision 7: published on 20th December 2012
• Revision 8: published by fencliff on 11th January 2013
• Revision 9: published on 28th February 2013 and last updated on 1st March 2013

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