irwin@oscar.ccm.udel.edu (11/15/89)
Hello friends, I am having a problem. I need to check for the existance of a card. I cannot 'go' to the card and check the result because I need to do the check in a closeCard handler. This has probably been discussed before but I cannot keep up with all these groups and get any work done. I am really supprised that there isn't a function 'the item exists' that would return true if the item was valid. I have poured over my literature for two days now and I would rather not brute force it. Thanx for your assistance Rich Irwin irwin@oscar.ccm.udel.edu Center for Composite Materials University of Delaware Newar, DE 19716
taylorj@yvax.byu.edu (11/21/89)
Easiest solution is to get SuperCard, which has an "exists" function. (I
really do hope this will be added to HyperCard 2.0).
Not so easy but more practical solution is something like this:
put false into cardExists
repeat with c = 1 to the number of cards
if the short name of card c = <the name of the card you're looking for> then
put true into cardExists
exit repeat
end if
end repeat
If this is what you meant by "brute force it," then I'm afraid you're out of
luck.
Jim Taylor
Microcomputer Support for Curriculum
Brigham Young University
taylorj@yvax.byu.edupsych@watserv1.waterloo.edu (R.Crispin - Psychology) (11/22/89)
A solution to the existance of a card that is short would be
set lockscreen to true
put the id of this card into oldiddrad
go to card cardname
if the result is not empty then
-- The card was not found
--do what ever you want here
go to card oldid
else
-- You will be at the card cardname
-- Do what ever you want here
end if
set lockscreen to false
Hope this helps
Richard Crispin
Dept. of Psych
Univ. of Waterloo
Waterloo, Ontariootim@hoptoad.uucp (Tim Maroney) (11/24/89)
In article <195@watserv1.waterloo.edu> psych@watserv1.waterloo.edu (R.Crispin - Psychology) writes: >A solution to the existance of a card that is short would be > > set lockscreen to true > put the id of this card into oldiddrad > go to card cardname > if the result is not empty then > go to card oldid > else > -- Do what ever you want here > end if > set lockscreen to false This does not answer the original question, since it will not work in a closeCard script -- it will recurse indefinitely. I have been watching the discussion and I've been wondering why no one pointed out that if you also "set lockMessages to true", then you should be able to get away with scooting over to another card, then scooting back, with no problems in a closeCard script. Am I overlooking something? -- Tim Maroney, Mac Software Consultant, sun!hoptoad!tim, tim@toad.com Feminism that refuses to use the word "patriarchy" is kin to abolitionism that refuses to use the word "slavery".
mmt@client1.DRETOR.UUCP (Martin Taylor) (11/24/89)
The dartmouth Xcmd stack (v3.1) has an ObjectExists XFCN that can tell
whether an object of a type known to HC exists (card, button, field, stack)
This is a much needed function if you are going to do repetitive things
on cards of different shapes. The stack is in the sumex archives for
ftp access.
--
Martin Taylor (mmt@zorac.dciem.dnd.ca ...!uunet!dciem!mmt) (416) 635-2048
If the universe transcends formal methods, it might be interesting.
(Steven Ryan).