Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!mcsun!cernvax!chx400!ugun2b!ugun2a!estier
From: estier@uni2a.unige.ch
Newsgroups: comp.sys.mac.hypercard
Subject: Re: Why no 'case' statement in Hypertalk?  Suggestions?
Message-ID: <1991Jun19.113253.998@uni2a.unige.ch>
Date: 19 Jun 91 09:32:53 GMT
Organization: University of Geneva, Switzerland
Lines: 46


In article <1991Jun4.234844.1280@cognet.ucla.edu> 
earl@cogdev.cognet.ucla.edu (Earl Williams) writes:
> Is there really no 'case' statement in Hypertalk, or am I missing its
> equivalent?  For simple keypress trapping, I'd like to do something like
> the following:
> 
> on keyDown key
>   case
>     key = 'a' then do this else
>     key = 'b' then do that else
>     key = 'c' then do the other
>   end
> end keyDown

In fact, there is no need of a case statement in HyperTalk since the 
handler mechanism can very conveniently be substituted to it. So instead of
writing borrowing sequences of "if-then-else-end if" for your example, why
not writing:

   on keyDown key
      if key is in "a b c" then send key
   end keyDown

   on a
     do this
   end a

   on b
     do that
   end b

   on c
     do the other
   end c

(Please don't write me that it takes too much time to execute, just wait 
 for the next (hopefully more powerfull)  Mac ;-)

 Thibault

+-----------------------------
| estier@macmail.unige.ch   or
| estier@cui.unige.ch       or
| ESTIER@CGEUGE51           
+-----------------------------