simple question about completion and case

[William Scott <wgscott@xxxxxxxxxxxxxxxxxx>]

Dear zsh folks:

Since I use Mac OS X, I wrote a very simple-minded completion
for the "open -a" command.

The command "open -a Foo" is the functional equivalent of clicking
on the application named Foo.  The -a specifies it is an application.


compctl -f -x 'p[2]' -s "(list of the applications available)" -- open


where list of the applications available contains elements like  Preview
and Mail and so on that are in title case.  It works ok.

I would like to be able to type

open -a preview

and have it corrected to

open -a Preview

Is there a way to do so for the open  command and not globally?  Sorry if
this
is obvious to everyone but me but I spent a fair amount of time with the
manual and experimenting to no avail.

Many thanks in advance.

Bill Scott