title: Lambda-Calculus Representation in NLTK CCG
body: <p>I am trying to implement a probabilistic ccg with lambda-calculus features.</p>
  
  <p>Basically i want to do the following code:</p>
  
  <pre><code>&gt;&gt; lex = parseLexicon(r'''
   :- S,NP
   He =&gt; NP {sem=\x.he(x)} [1.0]
   Walks =&gt; S\NP {sem=\X. walk(X)} [1.0]
   There =&gt; S\S {sem=\x . there(x)} [1.0]
   ''')
  &gt;&gt; parser = CCGChartParser(lex)
  &gt;&gt; all_parses = parser.nbest_parse(“He walks 
  there”.split(),n=100)
  &gt;&gt; for parse in all_parses: 
   printCCGDerivation(parse)
  </code></pre>
  
  <p>but existing CCG implementation of NLTK does not support {sem=\x.he(x)} [1.0] kinds of semantic parts in lexicon.</p>
  
  <p>Are there Any other CCG implementations that can handle this?
  Or can i represent this inside of NLTK?</p>