title: Make Prolog return one solution and stop showing the query option
body: <p>I'm new to prolog, and am experimenting with how to get it to stop querying after it finds one answer. I'm using this code:</p>
  
  <pre><code>member1(L,[L|_]).                    
  member1(L,[_|RS]) :- member1(L,RS),!.      
  </code></pre>
  
  <p>The result is:</p>
  
  <pre><code>| ?- member1(3,[3,2,3]).
  
  true ? a
  
  yes
  </code></pre>
  
  <p>I'm lost as to how I could get Prolog to stop printing "true ?" and just print "yes" instead. I've tried using if/else construct and the format function but it still prints "true ?". Any ideas?</p>