To meta-interpret a program in file <tt> File </tt>
  load the interpreter under prolog <tt>[meta]</tt>. The query is of
  the form <tt>go(File,Goal,Domain)</tt> where Goal is represented as
  a list of atoms and <tt>Domain</tt> is the name of the domain. 
  <p>

   Consider the program in the file <a href="ackermann">ackermann</a>
   which specifies the ackermann function.

    <pre>       
    under sicstus prolog:

    | ?- [meta]. 
    | ?- go(ackermann,[ackermann(s(s(0)),N,s(M))],concrete).

    M = s(s(0)),
    N = 0 ? ;

    M = s(s(s(s(0)))),
    N = s(0) ? ;

    M = s(s(s(s(s(s(0)))))),
    N = s(s(0)) ? ;

   etc.


    | ?- go(ackermann,[ackermann(even,one,R)],parity1).

    R = odd ? ;

    R = odd ? ;

    R = odd ? ;               

    etc                        
    </pre>