[SOLVED] LNAME - exctracting variables from stringed expression?

[DrD]

Prime can be confusing. If Han writes a book on the subject, I'm going to try to buy it!

Here's a few variations on the theme:

[CAS]
LNAME('X+y'); // ==> [X y] (vector)
lname('X+y'); // ==> Shows up as LNAME and returns {y} (list)

[Home]
LNAME('X+y'); // ==> Syntax error (we know why).
lname('X+y'); // ==> same deal.
LNAME("'X+y'"); // ==> {} blank as my mind.
lname("'X+y'"); // ==> same deal
CAS("lname('X+y');"); ==> [139,y] (previously X=139 here)
CAS("LNAME('X+y');"); ==>{y}

b:="X+y";
LNAME(CAS("CAS(b)")); // ==> {y}, the reserved variable X is not present.
b:=LOWER(b);
LNAME(CAS("CAS(b)")); // ==> {x,y}, life is good.

What I learn from this is that there is much to be learned.