title: valid characters for lisp symbols
body: <p>First of all, as I understand it variable identifiers are called symbols in common lisp.</p>
  
  <p>I noted that while in languages like C variable identifiers can only be alphanumberics and underscores, Common Lisp allows many more characters to be used like "*" and (at least scheme does) "?"</p>
  
  <p>So, what I want to know is: what exactly is the full set of characters that Common Lisp allows to have in a symbol (or variable identifier if I'm wrong)? is that the same for Scheme?</p>
  
  <p>Also, is the set of characters different for function names?</p>
  
  <p>I've been googling, looking in the CLHS, and in Practical Common Lisp, and for the life of me, something must be wrong because I can't seem to find the answer.</p>