variables tied with slurs

[Alexander Wallace]

Hi all, 

For study purposes, i want to do 128 rithmic patterns composed of 7 basic 
rithmic patterns combined via a tie.

Rather than writing the 128 patterns separately I'd love to write the basic 7 
as variables and then just reuse them.

Say that I write:

A = \drums { sn8 sn8 } 

How could I write the equivalent of 

\drums { sn8 sn8 ~ sn8 sn8 }

using variables?

This doesn't work:

{ \A ~ \A }

Is there any way?

Thank you so much in advance.