branch: externals/parser-generator
commit a60952c48277b8ff520479d6d7735ca15c9f825d
Author: Christian Johansson <christ...@cvj.se>
Commit: Christian Johansson <christ...@cvj.se>
More debugging of new algorithm
---
parser.el | 22 ++++++++++++++++------
1 file changed, 16 insertions(+), 6 deletions(-)
diff --git a/parser.el b/parser.el
index 3e44b1b..7986fad 100644
--- a/parser.el
+++ b/parser.el
@@ -586,6 +586,11 @@
(when (> first-length 0)
(push first first-list))))))
(setq first-list (sort first-list 'parser--sort-list))
+ (when (and
+ (not first-list)
+ (= (length β) 1)
+ (eq (car β) 'e))
+ (setq first-list '((e))))
first-list))))
;; Definition at p. 343
@@ -655,8 +660,8 @@
;; (a)
(dolist (rhs start-productions)
;; Add [S -> . α] to V(e)
- (push `(,start nil ,rhs e) lr-items-e)
- (puthash `(e ,start nil ,rhs e) t lr-item-exists))
+ (push `(,start nil ,rhs (e)) lr-items-e)
+ (puthash `(e ,start nil ,rhs (e)) t lr-item-exists))
(message "V(e): %s" lr-items-e)
@@ -685,25 +690,30 @@
;; Check if RHS starts with a non-terminal
(let ((rhs-first (car rhs)))
(when (parser--valid-non-terminal-p rhs-first)
+ (message "rhs-first: %s" rhs-first)
(let ((rhs-rest (append (cdr rhs) suffix)))
- (let ((rhs-first (parser--first rhs-rest)))
- (message "1b FIRST(%s) = %s" rhs-rest rhs-first)
+ (message "rhs-rest: %s" rhs-rest)
+ (let ((rhs-rest-first (parser--first rhs-rest)))
+ (message "1b FIRST(%s) = %s" rhs-rest rhs-rest-first)
(let ((sub-production (parser--get-grammar-rhs
rhs-first)))
;; For each production with B as LHS
(dolist (sub-rhs sub-production)
;; For each x in FIRST(αu)
- (dolist (f rhs-first)
+ (dolist (f rhs-rest-first)
;; Add [B -> . β, x] to v-set(e), provided it
is not already there
+ (message "f: %s" f)
(unless (gethash `(e ,rhs-first nil ,sub-rhs
,f) lr-item-exists)
+ (message "new-item: %s" `(,rhs-first nil
,sub-rhs ,f))
(puthash `(e ,rhs-first nil ,sub-rhs ,f) t
lr-item-exists)
(push `(,rhs-first nil ,sub-rhs ,f)
lr-items-e)
;; (c) Repeat (b) until no more items can be
added to v-set(e)
(setq found-new t))))))))))))))
- (puthash 'e lr-items-e lr-items))
+ (puthash 'e lr-items-e lr-items)
+ (message "V(e) = %s" lr-items-e))
;; 2 Suppose that we have constructed V(X1,X2,...,Xi-1) we construct
V(X1,X2,...,Xi) as follows:
(let ((prefix-acc)
