test-suite/lalr/test-lr-basics-02.scm

   1 ;;; test-lr-basics-02.scm --
   2 ;;
   3 ;;A grammar that only accept a single terminal or the EOI.
   4 ;;
   5
   6 (load "common-test.scm")
   7
   8 (define (doit . tokens)
   9   (let ((parser (lalr-parser (expect: 0)
  10                              (A)
  11                              (e (A) : $1
  12                                 ()  : 0))))
  13     (parser (make-lexer tokens) error-handler)))
  14
  15 (check
  16     (doit)
  17   => 0)
  18
  19 (check
  20     (doit (make-lexical-token 'A #f 1))
  21   => 1)
  22
  23 (check
  24     ;;Parse correctly the first A  and reduce it.  The second A triggers
  25     ;;an  error which  empties  the  stack and  consumes  all the  input
  26     ;;tokens.  Finally, the end-of-input token is correctly parsed.
  27     (let ((r (doit (make-lexical-token 'A #f 1)
  28                    (make-lexical-token 'A #f 2)
  29                    (make-lexical-token 'A #f 3))))
  30       (cons r *error*))
  31   => '(0 (error-handler "Syntax error: unexpected token : " . A)))
  32
  33 ;;; end of file