Hello,

I want to make a function in GAP that has as it's arguments 2 lists. The
function should perform some operations on these lists and return a boolean
value. However I want that the operations performed on the arguments
actually alter these arguments. So this function should have as a side
effect the alteration of these lists.
(like in Sort() for example)

However, every attempt either results in only altering the arguments within
the function but not on a higher level or I need to not give any arguments
and jsut make sure they exist outside the function with a fixed name. In
which case it still gives the "unbound golbal variable" error. This last
option isn't preferable to me.

Can anyone give me some insight in how to do this.
Thanks very much
-Chris