Re: syntax question

Tuesday, September 4, 2012

I've put up a test case on jsPerf:

Depending on the engine you might see varying results. You will also notice that your examples aren't the most efficient ones.

The fastest on Safari 6 is the member lookup.
The str in obj is slightly slower.
Regular expressions were the slowest in my case. You can get rid of the positive lookahead if you want exact match anyway to speed it up slightly.

I don't have the setup right here to test more browsers at the moment.


On Sun, Aug 26, 2012 at 8:29 PM, thor <> wrote:
Thank you, illandril!  :-)

On Saturday, August 25, 2012 12:12:12 PM UTC-5, illandril wrote:
With my tests...
Chrome 22: regular expressions
IE9: str in obj
FF11: str in obj

On Friday, August 24, 2012 10:53:05 PM UTC-4, thor wrote:
Which do you think is more efficient when checking if a string is either "<i>" or "<b>"?

  var obj = {'<b>': null, '<i>': null};
  var str = '<i>';

  var tag =<(?:b|i)>/);


  var tag = (str in obj);


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