[GAP Forum] Indeterminates

[Matthew Fayers]

Dear forum,

I have a custom package containing lots of functions that I use frequently, that I usually read into GAP at the start of every session.  Since I frequently use polynomials in one variable, one of the first lines of this package is

q:=Indeterminate(Rationals,"q");

The trouble is, if I modify the package and then re-read it into the session, GAP reads the line above again and assigns two indeterminates, both called q.  This causes problems for functions that refer to q.

Is there a way around this, apart from closing a re-opening GAP every time I update my package?  For example, is there a way to modify the above line so that it says something like "if q is not already assigned, let it be an indeterminate"?

Matt.

_____________________________________________________________________________________________
Matthew Fayers
School of Mathematical Sciences
Queen Mary, University of London
Mile End Road
London E1 4NS
020 7882 5479