NetNews Usenet Archive 1992 #30/NN_1992_30.iso/spool/comp/sys/mac/hypercar/4601

Internet Message Format | 1992-12-16 | 3.2 KB

Path: sparky!uunet!stanford.edu!apple!jkc
From: [e-mail] (John Kevin Calhoun)
Newsgroups: comp.sys.mac.hypercard
Subject: Re: HyperCard 2.1 and WorldScript
Message-ID: <[e-mail]>
Date: 17 Dec 92 02:43:01 GMT
References: <[e-mail]>
Organization: Apple Computer Inc, Cupertino, CA
Lines: 53


In article <[e-mail]> [e-mail]
(John Miller) writes:
>The postings about a new version [no, not the colour version :)]
>of HyperCard required for compatibility with System 7.1/WorldScript
>raises the question:  what are the incompatibilities between
>HyperCard 2.1 and 7.1?  Does anyone have any details?  I would
>be interested in incompatibilities that might affect normal
>user operations as well as anything that might apply to
>XCMDs localized to double-byte scripts such as Japanese.

First, the good news:  generally, you don't have anything to worry about
unless you install writing systems in a configuration that was previously
impossible.  For example, if your default writing system is Roman and one
of your secondary writing systems is Japanese, you'll have problems with
HyperCard's processing of Japanese text.  But if your default writing
system is Japanese and your secondary writing system is Roman, you won't
have any (new) problems.

Now, the complicated news:  here's the list of assumptions that HyperCard
2.1 makes about international system software that are all now problematic
under System 7.1 with WorldScript.

1) No more than two writing systems will be available on a machine at once.
2) If more than one writing system is available on a machine, the default
   writing system will not be Roman.
3) If special text characeristics, such as double-byte characters and
   bi-directional text, are supported by the system software, then they are
   supported by the default writing system only.
4) If the system software supports double-byte characters, then it's always
   necessary to scan all strings for double-byte characters.
5) When scanning strings for double-byte characters, it's always appropriate
   to use tables and routines provided by the default writing system.
6) If the preference setting in HyperCard's MLCB resource for using the
   internal replacement routines for TESetText and TECalText is true for
   the default writing system, then they're safe to use for all writing
   systems, even though they do not support bi-directional text.
7) Valid dates will be given or stored only in formats that are recognizable
   either in the default writing system or in Roman.
8) If the system software supports additional space characters (besides
   ascii $20), they will all be part of the default writing system.

Here's a list (possibly not exhaustive) of features that are implemented
in HC 2.1 with code that's based on one or more of these assumptions:

  String comparison, undo for typing runs, calculation of word breaks,
  counts of characters and words, evaluation of chunk expressions,
  drawing of fields, the keyDown message, the sort command, the find
  command, calculation of hash bits, conversion of dates between formats,
  "hot text", text pickup, backspacing over paint text, power keys.

Kevin Calhoun
[e-mail]