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Re: JavaScript: Trouble with switch Syntax

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"Gene Wirchenko" <genew@ocis.net> wrote in message 
news:ug4ie75gitc6gc9rsse94i0slcpumt1pg0@4ax.com...
> Dear JavaScripters:
>
>     I have hanged myself yet again with syntax.
>
>     Did you know that -- in IE9, at least -- you can use
>          otherwise
> instead of
>          default:
> in a switch statement?
>
>     Yes, you can.  It does not throw an error, but it also does not
> do anything.  Unless you count time wasted looking for a bug.
>
>     I may as well ask if anyone else has committed such bogosities.
>
Not that particular one, but plenty of others.

'otherwise' (without the quotes) on a line by itself, presumably following a 
'break;'will trigger Javascript/JScript/ECMAscript's default behaviors:
(1) 'otherwise' is not a reserved word, therefore it is an identifier;
(2) the identifier 'otherwise' is not declared locally (in a 'var' 
statement), therefore it must be a property attached to the global object 
(and created there if not found);
(3) end of line has been encountered, therefore a semicolon must have been 
intended (!) and will be supplied by the language processor.

That 'otherwise' has successfully instantiated a property on the global 
object with initial value 'undefined', which is consumed in place by the 
semicolon (basically, it is an expression whose value is ignored). Not a 
problem!

If it had been the case that 'otherwise' had a colon following it 
(otherwise:), then that would have been a statement label; again, no problem 
at all!

Such a nice language processor, so eager to please!

The syntax of Javascript draws heavily from the C language (not Pascal). I 
use Firefox a lot, and I have found the Mozilla Developer Network website 
particularly helpful:

https://developer.mozilla.org/en/JavaScript/Reference

For JScript, the Microsoft Developer Network is a good start point:

http://msdn.microsoft.com/en-us/library/yek4tbz0%28v=VS.85%29.aspx

and W3C gets me pointed at DOM/XML/XSL :

http://www.w3.org/standards/

I also spent time looking at
http://www.jslint.com/ <<--!! very useful !!
http://javascript.crockford.com/
http://helephant.com/2008/08/17/how-javascript-objects-work/
http://jibbering.com/faq/notes/closures/
http://bonsaiden.github.com/JavaScript-Garden/

c.l.j contributors John Harris and John Stockton also have online resources 
available.
There are doubtless others as well, and I intend no slight by my lack of 
knowledge.

Learn and grow, share and enjoy! 

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JavaScript: Trouble with switch Syntax Gene Wirchenko <genew@ocis.net> - 2011-12-14 13:23 -0800
  Re: JavaScript: Trouble with switch Syntax Jake Jarvis <pig_in_shoes@yahoo.com> - 2011-12-14 23:32 +0100
    Re: JavaScript: Trouble with switch Syntax Tim Streater <timstreater@greenbee.net> - 2011-12-14 22:39 +0000
    Re: JavaScript: Trouble with switch Syntax Gene Wirchenko <genew@ocis.net> - 2011-12-14 18:11 -0800
      Re: JavaScript: Trouble with switch Syntax Dr J R Stockton <reply1150@merlyn.demon.co.uk> - 2011-12-16 21:28 +0000
  Re: JavaScript: Trouble with switch Syntax "Aaron Sawyer" <aaron.sawyer@deltaware.com> - 2011-12-14 18:58 -0400
    Re: JavaScript: Trouble with switch Syntax Jake Jarvis <pig_in_shoes@yahoo.com> - 2011-12-15 00:42 +0100
      Re: JavaScript: Trouble with switch Syntax Jake Jarvis <pig_in_shoes@yahoo.com> - 2011-12-15 01:06 +0100
    Re: JavaScript: Trouble with switch Syntax Gene Wirchenko <genew@ocis.net> - 2011-12-14 18:09 -0800
      Re: JavaScript: Trouble with switch Syntax Ross McKay <au.org.zeta.at.rosko@invalid.invalid> - 2011-12-15 18:33 +1100

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