Path: utzoo!attcan!uunet!lll-winken!lll-lcc!ames!claris!apple!dan
From: dan@Apple.COM (Dan Allen)
Newsgroups: comp.sys.mac.hypercard
Subject: Re: efficient cardExists function
Message-ID: <12258@apple.Apple.COM>
Date: 16 Jun 88 04:45:23 GMT
References: <5888@bunny.UUCP>
Reply-To: dan@apple.apple.com.UUCP (Dan Allen)
Organization: Apple Computer Inc, Cupertino, CA
Lines: 26

In article <5888@bunny.UUCP> jwg1@bunny.UUCP (James W. Gish) writes:
>I need a function, cardExists( cardName ), that will return true iff 
>a card of name cardName exists in the stack.  
>
>So far, the only thing I could come up with is a repulsively slow 
>linear search that compares cardName with the name of each card in
>the stack.

How about something like
	push this card
	get id of this card
	go card "foo" -- where foo is your card name
	if it is not the id of this card then
		pop card -- to get you back where you were
		-- set some variable so you know the card exists
	else
		-- card does not exist, set a variable or whatever
	end if

I haven't tried it but something along these lines should use the full
power of HyperCard's fast search when you say go card "foo" and the rest
is just error checking.  I'm sure there are a variety of ways to check
where you are or were or whatever....

Dan Allen
Software Explorer
Apple Computer