List of variables within script?

["Jim Jones" <jjones@...>]

Is there any way to evaluate a script and obtain a list of its defined
variables without fully executing the script or writing my own parsing
engine?

If someone defines the following script, there is no reason I should have to
execute that entire looping structure to determine that x and y are
variables members.

x = 1
while x < 10000000 do
 x = x + 1
 y = sqrt(x)
end


Any insight is certainly appreciated.

Jim