;;; test-lr-associativity-04.scm -- ;; ;;Show how to use associativity. ;; (load "common-test.scm") (define (doit . tokens) (let ((parser (lalr-parser (expect: 0) (N (left: A) (left: M)) (E (N) : $1 (E A E) : (list $1 $2 $3) (E A E A E) : (list (list $1 $2 $3) $4 $5) (E M E) : (list $1 $2 $3) (E M E M E) : (list $1 $2 (list $3 $4 $5)) (E A E M E) : (list $1 $2 $3 $4 $5) (E M E A E) : (list $1 $2 $3 $4 $5) )))) (parser (make-lexer tokens) error-handler))) ;;; -------------------------------------------------------------------- ;;; Single operator. (check (doit (make-lexical-token 'N #f 1)) => 1) (check (doit (make-lexical-token 'N #f 1) (make-lexical-token 'A #f '+) (make-lexical-token 'N #f 2)) => '(1 + 2)) (check (doit (make-lexical-token 'N #f 1) (make-lexical-token 'M #f '*) (make-lexical-token 'N #f 2)) => '(1 * 2)) ;;; -------------------------------------------------------------------- ;;; Precedence. (check (doit (make-lexical-token 'N #f 1) (make-lexical-token 'A #f '+) (make-lexical-token 'N #f 2) (make-lexical-token 'M #f '*) (make-lexical-token 'N #f 3)) => '(1 + (2 * 3))) (check (doit (make-lexical-token 'N #f 1) (make-lexical-token 'M #f '*) (make-lexical-token 'N #f 2) (make-lexical-token 'A #f '+) (make-lexical-token 'N #f 3)) => '((1 * 2) + 3)) ;;; -------------------------------------------------------------------- ;;; Associativity. (check (doit (make-lexical-token 'N #f 1) (make-lexical-token 'A #f '+) (make-lexical-token 'N #f 2) (make-lexical-token 'A #f '+) (make-lexical-token 'N #f 3)) => '((1 + 2) + 3)) (check (doit (make-lexical-token 'N #f 1) (make-lexical-token 'M #f '*) (make-lexical-token 'N #f 2) (make-lexical-token 'M #f '*) (make-lexical-token 'N #f 3)) => '((1 * 2) * 3)) ;;; end of file