Hi guys, I recently started using ginac, and one thing I couldnt figure out from the tutorial is how can I make an expression one piece at a time.  So if I wanted to build an expresison out of a list like x,=,5,*,4

I imagine doing something like
ex expr;
expr.append(x);
expr.append(==);
expr.append(5);
expr.append(4);

I understand the numbers are numerics, and x would be a symbol, but I dont know what the operators would be ( *   /   +  - ).

Does anyone how I can do this?  Does this even make any sense to you?  Thanks for any replies!

R. Gordon