title: Prolog dcg generating all words from language
body: <p>I'm trying to write some dcg grammar in prolog which will describe language of<br>
  <code>a^nb^n n&gt;=0</code><br>
  <code>"",ab,aabb,aaabbb itd</code></p>
  
  <p>All what I wrote is </p>
  
  <pre><code>s --&gt; slowo.
  slowo --&gt; [a],slowo,[b],!.
  slowo --&gt; [].  
  </code></pre>
  
  <p>And its good as long as all I want to do is just check if word is correct, but how should dcg grammar look in prolog for <code>?-phrase(s,X)</code> which will generate all words from my language?</p>