From: Mark Slagell <ms@...>
Date: 2001-05-22T01:11:23+09:00
Subject: [ruby-talk:15492] Re: ranges & case

ts spake:
> 
> >>>>> "M" == Mark Slagell <ms@iastate.edu> writes:
> 
> M> We don't have open-ended ranges; is it possible to accurately express
> M> this without resorting to if...elsif...end?
> 
>  If you don't want if ... elsif
> 
>     case
>     when p > 100
>        "right"
>     when p > -100
>        "center"
>     else
>        "left"
>     end
> 
> Guy Decoux


Ah. Hadn't thought of a naked-case like that. But since it doesn't
factor the 'p' out, I'm not sure what it buys me.

It just occurred to me that infinity could be used in a range.

   c = case p
         when (100 .. (+1.0/0))     then "right"
         when (-100 .. 100)         then "center"
         when ((-1.0/0) .. -100)    then "left"
       end