From: Florian Gilcher <flo@...>
Date: 2008-04-19T21:11:06+09:00
Subject: Re: if behavior

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On Apr 19, 2008, at 1:57 PM, Qwe Qwe wrote:

> Hi,
> i recently started to learn ruby as well as rails and came across a
> problem.
> such code:
> [code]
> if session[:login]
>   10/0
> else
>   11/0
> end if
> [/code]
> doesn't inform me about division by zero. Actually it seems that  
> none of
> paths is evaluated. I don't get it. I've checked few tutorials, none  
> of
> the said anything about possibility of such behavior.
> -- 
> Posted via http://www.ruby-forum.com/.
>

Yes, because the code never gets evaluated. if-blocks are ended by  
"end" and not "end if". What you wrote can be interpreted as:

====
(if session[:login]
   10/0
else
   11/0
end) if
====

So: execute the if statement, if.... As there is no second condition  
on the second if, it is always false. So the code inside the  
paranthesis will never get executed.

This is happening because ruby allows you to write a condition after a  
statement, e.g.:

====
do_weird_things if (true == ruby.is_driving_crazy?(you))
====

Regards,
Florian Gilcher
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