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From: ns@cat.cmu.edu (Nicholas Spies)
Newsgroups: comp.sys.mac.hypercard
Subject: Re: Sorting by multiple keys
Message-ID: <4388@pt.cs.cmu.edu>
Date: 1 Mar 89 17:44:28 GMT
References: <2053@tank.uchicago.edu>
Distribution: usa
Organization: Carnegie-Mellon University, CS/RI
Lines: 20

In article <2053@tank.uchicago.edu> ben@rover.bsd.uchicago.edu writes:
>I want to sort my cards by two "keys"...

You can sort by concatenating the contents of fields
(e.g. sort by field "a" & field "b")

In fact, you can sort by the result of an expression or function, so long as
the expression or function can be applied to each card. Thus

sort by field "xx" is empty & field "xx" -- will sort by field "xx", but put
empty field "xx" cards at the end (rather than the beginning) of the stack.
Why? Because -- field "xx" is empty -- evaluates to either TRUE or FALSE.

The same technique can be used using functions.


-- 
Nicholas Spies			ns@cat.cmu.edu.arpa
Center for Design of Educational Computing
Carnegie Mellon University
--