The following is a problem with both maxima 5.5 and the commercial macsyma. What would it take to fix it? Dan Stanger (C1) f(x):=x::1; (D1) f(x) := x :: 1 (C2) f(x); (D2) 1 (C3) x; (D3) x x is not assigned to. (C4) y; (D4) y (C5) f(y); (D5) 1 (C6) y; (D6) 1 However y is.