title: Getting hashes of any type of objects in Common Lisp
body: <p>I'm trying to implement some data structures (like HAMP-hash array mapped trie) in Common Lisp and I need to get 32- or 64-bit hashes of objects which I want to store in these data structures.</p>
  
  <p>I know I can put objects into Common Lisp hash tables (created with <code>(make-hash-table)</code>), but I couldn't find a way to get a hash of an object, like <code>hashCode</code> of Java or <code>hash</code> of Python.  Does Common Lisp have a function like that?  If doesn't, how does CL's standard hash table generate hashes from arbitrary types of objects?</p>