HCoop / bpt / guile.git / blame
| Commit | Line | Data |
|---|---|---|
| 1b101522 LC |
1 | ;;; test-lr-associativity-01.scm -- |
| 2 | ;; | |
| 3 | ;;Show how to use left and right associativity. Notice that the | |
| 4 | ;;terminal M is declared as right associative; this influences the | |
| 5 | ;;binding of values to the $n symbols in the semantic clauses. The | |
| 6 | ;;semantic clause in the rule: | |
| 7 | ;; | |
| 8 | ;; (E M E M E) : (list $1 $2 (list $3 $4 $5)) | |
| 9 | ;; | |
| 10 | ;;looks like it is right-associated, and it is because we have declared | |
| 11 | ;;M as "right:". | |
| 12 | ;; | |
| 13 | ||
| 14 | (load "common-test.scm") | |
| 15 | ||
| 16 | (define (doit . tokens) | |
| 17 | (let ((parser (lalr-parser | |
| 18 | (expect: 0) | |
| 19 | (N (left: A) | |
| 20 | (right: M) | |
| 21 | (nonassoc: U)) | |
| 22 | (E (N) : $1 | |
| 23 | (E A E) : (list $1 $2 $3) | |
| 24 | (E M E) : (list $1 $2 $3) | |
| 25 | (E M E M E) : (list $1 $2 (list $3 $4 $5)) | |
| 26 | (A E (prec: U)) : (list '- $2))))) | |
| 27 | (parser (make-lexer tokens) error-handler))) | |
| 28 | ||
| 29 | ;;; -------------------------------------------------------------------- | |
| 30 | ;;; Single operator. | |
| 31 | ||
| 32 | (check | |
| 33 | (doit (make-lexical-token 'N #f 1)) | |
| 34 | => 1) | |
| 35 | ||
| 36 | (check | |
| 37 | (doit (make-lexical-token 'N #f 1) | |
| 38 | (make-lexical-token 'A #f '+) | |
| 39 | (make-lexical-token 'N #f 2)) | |
| 40 | => '(1 + 2)) | |
| 41 | ||
| 42 | (check | |
| 43 | (doit (make-lexical-token 'N #f 1) | |
| 44 | (make-lexical-token 'M #f '*) | |
| 45 | (make-lexical-token 'N #f 2)) | |
| 46 | => '(1 * 2)) | |
| 47 | ||
| 48 | (check | |
| 49 | (doit (make-lexical-token 'A #f '-) | |
| 50 | (make-lexical-token 'N #f 1)) | |
| 51 | => '(- 1)) | |
| 52 | ||
| 53 | ;;; -------------------------------------------------------------------- | |
| 54 | ;;; Precedence. | |
| 55 | ||
| 56 | (check | |
| 57 | (doit (make-lexical-token 'N #f 1) | |
| 58 | (make-lexical-token 'A #f '+) | |
| 59 | (make-lexical-token 'N #f 2) | |
| 60 | (make-lexical-token 'M #f '*) | |
| 61 | (make-lexical-token 'N #f 3)) | |
| 62 | => '(1 + (2 * 3))) | |
| 63 | ||
| 64 | (check | |
| 65 | (doit (make-lexical-token 'N #f 1) | |
| 66 | (make-lexical-token 'M #f '*) | |
| 67 | (make-lexical-token 'N #f 2) | |
| 68 | (make-lexical-token 'A #f '+) | |
| 69 | (make-lexical-token 'N #f 3)) | |
| 70 | => '((1 * 2) + 3)) | |
| 71 | ||
| 72 | ;;; -------------------------------------------------------------------- | |
| 73 | ;;; Associativity. | |
| 74 | ||
| 75 | (check | |
| 76 | (doit (make-lexical-token 'N #f 1) | |
| 77 | (make-lexical-token 'A #f '+) | |
| 78 | (make-lexical-token 'N #f 2) | |
| 79 | (make-lexical-token 'A #f '+) | |
| 80 | (make-lexical-token 'N #f 3)) | |
| 81 | => '((1 + 2) + 3)) | |
| 82 | ||
| 83 | (check | |
| 84 | (doit (make-lexical-token 'N #f 1) | |
| 85 | (make-lexical-token 'M #f '*) | |
| 86 | (make-lexical-token 'N #f 2) | |
| 87 | (make-lexical-token 'M #f '*) | |
| 88 | (make-lexical-token 'N #f 3)) | |
| 89 | => '(1 * (2 * 3))) | |
| 90 | ||
| 91 | ;;; end of file |