anchor.diff:                       (yacc-parse-error-expected-terminals e)))))
   
   (defun parse-with-lexer (lexer parser)
  +"Parse the stream of symbols provided by LEXER using PARSER.
  +LEXER is a function of no arguments returning a symbol and a semantic value,
  +and should return (VALUES NIL NIL) when the end of input is reached.
  +Handle YACC-PARSE-ERROR to provide custom error reporting."
     (declare (type (function () (values symbol t)) lexer))
     (declare (type parser parser))
     (let ((action-array (parser-action parser))
  
positive.code:       (return t))))
  
  (defun sequence-derives-epsilon (sequence grammar)
    (declare (list sequence) (type grammar grammar))
    (every #'(lambda (s) (derives-epsilon s grammar)) sequence))
  
  
negative.code:      collection)))
  
  (defun lr1-add-collection (items collection)
    "Add all the elements of ITEMS to COLLECTION."
    (declare (type lr1-collection items collection))
    (typecase items
      (list
  