branch: externals/parser-generator
commit 1ae36fc70b4f8a6aae9f7a694bc567899178beca
Author: Christian Johansson <christ...@cvj.se>
Commit: Christian Johansson <christ...@cvj.se>
Added support for calculating first of a sentential form
---
parser.el | 3 +--
test/parser-test.el | 18 +++++++++++++-----
2 files changed, 14 insertions(+), 7 deletions(-)
diff --git a/parser.el b/parser.el
index b153d84..60eb3ab 100644
--- a/parser.el
+++ b/parser.el
@@ -498,8 +498,7 @@
;; Iterate each symbol in β using a PDA algorithm
(let ((input-tape β)
(input-tape-length (length β))
- (stack '((0 0 nil)))
- (first-list nil))
+ (stack '((0 0 nil))))
(while stack
(let ((stack-topmost (pop stack)))
(parser--debug
diff --git a/test/parser-test.el b/test/parser-test.el
index 1a2b2fc..80d81b4 100644
--- a/test/parser-test.el
+++ b/test/parser-test.el
@@ -35,11 +35,19 @@
(parser--first 'S)))
(message "Passed first 1 with rudimentary grammar")
- ;; (should
- ;; (equal
- ;; '((a a))
- ;; (parser--first '(S a))))
- ;; (message "Passed first 1b with rudimentary grammar")
+ (parser--set-grammar '((S) (a) ((S a)) S) 1)
+ (should
+ (equal
+ '((a))
+ (parser--first '(S a))))
+ (message "Passed first 1b with rudimentary grammar")
+
+ (parser--set-grammar '((S) (a) ((S a)) S) 2)
+ (should
+ (equal
+ '((a a))
+ (parser--first '(S a))))
+ (message "Passed first 1c with rudimentary grammar")
(parser--set-grammar '((S) ("a" "b" "c") ((S ("a" "b" "c"))) S) 2)
(should
