From: dohzya <dohzya@...>
Date: 2007-09-08T19:21:48+09:00
Subject: Re: #to_b - why isn't this one already in there?

Le samedi 08 septembre 2007 � 11:01 +0900, Giles Bowkett a �crit :
> everybody knows
> 
> if "false"
> 
> returns true. there are situations where that's a pain. I did a Rails
> thing where I was creating objects and calling methods from options
> hashes which I sometimes got by simply passing in params from a
> controller and sometimes actually wrote as code. so I would have
> 
> @some_boolean = options[:some_boolean]
> 
> and five minutes later I'd be stubbing my metaphorical toe on an
> 
> if "false"
> 
> statement.
> 
> so I changed it to this:
> 
> @some_boolean = options[:some_boolean].to_b
> 
> and implemented #to_b by doing this:
> 
> class String
>   def to_b
>     case self
>     when "true"
>       true
>     when "false"
>       false
>     else
>       raise Exception
>     end
>   end
> end
> 
> class FalseClass
>   def to_b
>     false
>   end
> end
> 
> class TrueClass
>   def to_b
>     true
>   end
> end
> 
> at that point I could pass in options hashes and it didn't matter
> whether they came in properly and correctly as actual boolean values
> or blustered in the servants' entrance as URL parameters.
> 
> what's weird to me about that is, it's so obvious, so useful, and so
> trivial that I don't understand why it isn't the language to begin
> with. obviously it comes from the inspiration of #to_s, #to_i, etc.
> anyone who's ever written
> 
> if foo == "false"
> 
> can see the usefulness of this.
> 

Hi,
why "false" would be false when "" is true ?
There are just 2 values for false : nil and false.
Others would introduce confusion...

Use a function/method to convert your string in boolean with some
rules, 
but don't change the ruby philosophy !

< of course, it's just my opinion ;) >

--
Etienne Vallette d'Osia