Comments for Jason Clawson

Comment on Javascript ‘==’ operator and indexOf failure by Rob

Rob — Wed, 08 Apr 2009 16:16:24 +0000

Type coercion seems to be Bad, at least as far as Douglas Crockford is concerned. Check out http://www.jslint.com/lint.html (scroll down to “== and !=”).

Comment on Stark Industries - “The process” by Mike

Mike — Mon, 30 Mar 2009 16:46:59 +0000

Very very funny. I used to work at Stark Industries and know full well the pain you describe in your couple of articles. How true it all is - esp. the process weenies. Those people must get a free lobotomy included with their hiring.

Comment on ExtJS Performance - Element click events by Luis

Luis — Tue, 17 Mar 2009 05:30:41 +0000

Absolutely!!

Great!!! Thanks!!

Comment on Javascript ‘==’ operator and indexOf failure by Radomir

Radomir — Sun, 01 Mar 2009 22:00:02 +0000

wasn’t there a new release for this?

Comment on ExtJS - Update to ComboBox Replacement by Roberto

Roberto — Mon, 19 Jan 2009 19:56:30 +0000

Your component override works like a charm!
In my case just had to disable (comment code):
cfg.mode = “remote”;

and set some values to false :
autoLoad : false,
forceSelection:false,

I had spent one day trying to figure out that ExtJS hiddenName property didnt work properly
Thank you for sharing.

Comment on ExtJS Performance - Element click events by Neto

Neto — Tue, 06 Jan 2009 12:20:50 +0000

Cara, eu precisava disso, obrigado!!!

(Translated: “Man, I needed it, thanks!”)

Comment on ExtJS Performance - Event Listener Cleanup by Joshua

Joshua — Sat, 06 Dec 2008 13:48:59 +0000

Great tip! I know you said you were going to post some more, so?

Comment on Javascript ‘==’ operator and indexOf failure by Jason

Jason — Sat, 26 Jul 2008 15:43:56 +0000

Yeah I know… this bug is really pervasive across libraries and no one really notices! Here is the link to the bug report for ExtJS: http://extjs.com/forum/showthread.php?t=40040

Comment on Javascript ‘==’ operator and indexOf failure by Juan Mendes

Juan Mendes — Wed, 23 Jul 2008 16:17:25 +0000

Point taken. I would have figured prototype, ext-js and jquery would know better than to use double equals for an equality test in a very generic function.

Comment on Javascript ‘==’ operator and indexOf failure by Jason

Jason — Wed, 23 Jul 2008 13:11:36 +0000

To say that == functionality is a bug I suppose can be considered incorrect only by the fact that this functionality is documented. But you hit on my point exactly; it’s not how most programmers expect it to behave. Good programming languages should be predictable and useful in the way they behave.

You also said you take care to always use ‘===’ in most cases. ‘===’ is hardly the de facto standard equality comparison operator. Just by the fact that you have to consciously make a decision to use the triple equals to “avoid problems like [this]” indicates an inherent problem with the ‘==’ implementation. Simply put, it doesn’t do what you want nor expect. I call that a bug.

The conversion of types functionality is not particularly useful in so far as comparing objects or functions to primitive types and strings. The only use for type conversion is in comparing a number to a string that contains a number: 6.2 == “6.2″ Therefore, I consider this a bug. Most, if not all other scripting languages, convert between primitives but do type checking for objects.

Further supporting this as a bug is that no other language (to my knowledge… please correct me if I am wrong and I very well could be since I have not used every scripting language ;-)) behaves this way except for ECMA script.

To suggest that this is common knowledge is definitely incorrect since every major javascript library currently implements indexOf using ‘==’ instead of ‘===’ which is incorrect.

I am glad that you use ‘===’ and that you are aware of the pitfalls of ‘==’. However, I would venture to guess that 90% of developers out there do not know this and do not have any idea that the libraries they are using implement indexOf incorrectly.