test-suite/lalr/test-glr-basics-01.scm

   1 ;;; test-lr-basics-01.scm --
   2 ;;
   3 ;;A grammar that only accept a single terminal as input.  It refuses the
   4 ;;end-of-input as first token.
   5 ;;
   6
   7 (load "common-test.scm")
   8
   9 (define (doit . tokens)
  10   (let* ((lexer         (make-lexer tokens))
  11          (parser        (lalr-parser (expect: 0)
  12                                      (driver: glr)
  13                                      (A)
  14                                      (e (A) : $1))))
  15     (parser lexer error-handler)))
  16
  17 (check
  18     (doit (make-lexical-token 'A #f 1))
  19   => '(1))
  20
  21 (check
  22     (doit)
  23   => '())
  24
  25 (check
  26     ;;Parse correctly the first A  and reduce it.  The second A triggers
  27     ;;an  error which  empties  the  stack and  consumes  all the  input
  28     ;;tokens.   Finally, an  unexpected end-of-input  error  is returned
  29     ;;because EOI is invalid as first token after the start.
  30     (doit (make-lexical-token 'A #f 1)
  31           (make-lexical-token 'A #f 2)
  32           (make-lexical-token 'A #f 3))
  33   => '())
  34
  35 ;;; end of file