From: "Kroeger, Simon (ext)" <simon.kroeger.ext@...>
Date: 2006-04-11T22:30:16+09:00
Subject: Re: Smalltalk's favorite Boolean method

 

> -----Original Message-----
> From: list-bounce@example.com 
> [mailto:list-bounce@example.com] On Behalf Of Ernest Micklei
> Sent: Tuesday, April 11, 2006 3:13 PM
> To: ruby-talk ML
> Subject: Smalltalk's favorite Boolean method
> 
> Hi,
> 
> For a long time I have been programming Smalltalk.
> Recently, Ruby "got me" and I was wondering how the
> famous ifTrue:ifFalse: could be added to the System.
> 
> 1 = 2
>   ifTrue:
>    [Transcript show: "true!" ]
>   ifFalse:
>    [Transcript show: "false!"]
> [...] 

What about:
----------------------------------
def true.ifTrue
  yield; self
end

def true.ifFalse
  self
end

def false.ifTrue
  self
end

def false.ifFalse
  yield; self
end

(1==2).
  ifTrue {p "true!"}.
  ifFalse {p "false!"}
    
(1!=2).
  ifTrue {p "true!"}.
  ifFalse {p "false!"}
----------------------------------

But note that in ruby not only true is 'true' 
but every object other than nil or false. 

cheers

Simon