Use of variables in the <x-y> globbing mechanism

[Henman <dhenman@gmail.com>]

It would be very useful if  the <x-y> globbing mechanism would work with 
variables.   I can't get it to work.  If it only accepts numeric 
constants, nothing can be done, but it would be an elegant solution to 
my problem of taking a slice of files out of a larger group for 
processing in a batch file.


I am trying to do this:   ( Where the Src FName Patter  SFNPAT gives the 
fname prefix and fname extension and the <01-15> specifies which slice 
of files to get.
# The from_number and to_number are read in from a list of files to process
     and injected between a filename pattern's prefix and extension.

    for file in ${SFNPAT:r}-<${from_number}-${to_number}>.${SFNPAT:e}
       do
           # processing goes here
       done

When I try the above script, I am greeted with a  " parse error near 
`<'"    error message.  This can be done otherways, I just wanted to 
know if the <X-Y> form could be used in some way to acheive this.

Thanks