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Best practice for naming of options

• To: mathgroup at smc.vnet.net
• Subject: [mg71473] Best practice for naming of options
• From: "Andrew Moylan" <andrew.j.moylan at gmail.com>
• Date: Mon, 20 Nov 2006 06:17:06 -0500 (EST)

Hi all,

When writing my own functions that use options, I sometimes have a
problem where option names become shadowed by other packages that are
loaded later. For example, I might want to use an option called
ScaleFunction:

BeginPackage["MySpace`"];
ScaleFunction::"usage" = "hello";
EndPackage[];

Needs["Graphics`"]

Now the name ScaleFunction is shadowed by the option of the same name
from the Graphics package:

Evaluating
  ? ScaleFunction
gives
  Graphics`Common`GraphicsCommon`ScaleFunction

I can think of two possible solutions to this problem, each with a
different problem:

(1) I could try to always choose unique names for my options. This
produces cumbersome option names and in any case only works until I or
someone else writes a package with that option name.

(2) I could use _strings_ for option names instead of symbols:
Func["ScaleFunction" -> x] instead of Func[ScaleFunction -> x]. I have
seen this done sometimes in the built-in Mathematica functions.
Unfortunately, with this approach it no longer becomes possible to
define usage text for options in the usual way:

  "ScaleFunction"::usage = "ScaleFunction is an option to Func that
...";
gives the warning
  Message::name : Message name ScaleFunction::usage is not of the form
\
symbol::name or symbol::name::language.

Is there a way to get the best of both worlds (define usage strings AND
ensure that option names don't become shadowed)?

Cheers,
Andrew

P.S. I observe that the built-in function NSum has an option called
NSumTerms. I think this option would be better called Terms. Could it
be that the writers of that function faced the same dilemma that I am
facing?