Availability:built-in
variable_names and return the read term in Term 
and the variable bindings in Bindings. Bindings is 
a list of
Name = Var couples, thus providing 
access to the actual variable names. See also read_term/2. 
If Atom has no valid syntax, a syntax_error 
exception is raised. New code should use
read_term_from_atom/3.