Now a word on the maple data types function and expression. Maple does not make a diffence between functions in the usual sence and procedures. So we have to force the evaluation. We used to have full evaluation for locals. This was just intolerable.
Lexical closures is on the list of key features to implement.
I very much want it. In Gauss I use them all the time, I simulate them but substitution. Now let's define a function 'g' which is the derivative of 'f'. It also tells you if there is a remember table or not, and asks you if you want to print it.