lol I get what you are trying to say Roman.

As a numerical value the absence of a + implies a positive numerical value, while a negative one must be preceded by -.

I guess I don't have a choice but to pass this argument as a string since in the markup I want to translate, I want to be able to do the following:

<size 12<text> => explicit size increase

<size +2<text> => relative size increase (ie: the base font size is 10, and want to increase it by 2 to 12pt)

<size -2<text> => relative size decrease

So I will need to convert the above markup from the input stream into the following Lisp form

(size "12" "text")

(size "+2" "text")

passing the first argument as a string for this to work....ok should be easy enough.