branch: elpa/parseclj
commit ff0443c27c2ee0d5caa8f931ad5344ae494d65b1
Author: Arne Brasseur <[email protected]>
Commit: Arne Brasseur <[email protected]>
Add :read-one option
Adds an option, `:read-one t`, which makes the parser behaves more like a
LISP
`read` function: it will read a single form and return it.
In this case there is no extra `:root` node, the parsed node is returned
directly.
---
parseclj-parser.el | 28 +++++++++++++++++++++++-----
parseclj.el | 4 +++-
test/parseclj-test.el | 17 +++++++++++++++++
3 files changed, 43 insertions(+), 6 deletions(-)
diff --git a/parseclj-parser.el b/parseclj-parser.el
index ef04e16ef7..d0e5d24a21 100644
--- a/parseclj-parser.el
+++ b/parseclj-parser.el
@@ -149,6 +149,18 @@ TOKEN-TYPES are the token types to look for."
(t
(push (pop stack) result)))))))
+(defun parseclj-single-value-p (stack value-p)
+ "Return t if STACK only has a single node for which VALUE-P is true.
+
+This checks if the stack contains a single, fully reduced value, and no
+dangling unmatched tokens. When parsing with `:read-one' this indicates a
+form can be returned."
+ (and (not (cl-reduce (lambda (bool node)
+ (or bool (parseclj-lex-token-p node)))
+ stack
+ :initial-value nil))
+ (parseclj--take-value stack value-p)))
+
(defun parseclj-parser (reduce-leaf reduce-branch &optional options)
"Clojure/EDN stack-based shift-reduce parser.
@@ -186,13 +198,17 @@ functions. Additionally the following options are
recognized
- `:tag-readers'
An association list that describes tag handler functions for any possible
tag. This options in only available in `parseedn-read', for more
- information, please refer to its documentation."
+ information, please refer to its documentation.
+- `:read-one'
+ Return as soon as a single complete value has been read."
(let ((fail-fast (a-get options :fail-fast t))
+ (read-one (a-get options :read-one))
(value-p (a-get options :value-p (lambda (e) (not
(parseclj-lex-token-p e)))))
(stack nil)
(token (parseclj-lex-next)))
- (while (not (eq (parseclj-lex-token-type token) :eof))
+ (while (not (or (and read-one (parseclj-single-value-p stack value-p))
+ (eq (parseclj-lex-token-type token) :eof)))
;; (message "STACK: %S" stack)
;; (message "TOKEN: %S\n" token)
@@ -252,9 +268,11 @@ functions. Additionally the following options are
recognized
(a-get token :pos)
(parseclj-lex-token-type token))))
- (car (funcall reduce-branch nil (parseclj-lex-token :root "" 1)
- (reverse stack)
- options))))
+ (if read-one
+ (car (parseclj--take-value stack value-p))
+ (car (funcall reduce-branch nil (parseclj-lex-token :root "" 1)
+ (reverse stack)
+ options)))))
(provide 'parseclj-parser)
;;; parseclj-parser.el ends here
diff --git a/parseclj.el b/parseclj.el
index 6a4849dd6c..5a0743141e 100644
--- a/parseclj.el
+++ b/parseclj.el
@@ -45,7 +45,9 @@ key-value pairs to specify parsing options.
- `:lexical-preservation' Retain whitespace, comments, and
discards. Defaults to nil.
- `:fail-fast' Raise an error when encountering invalid syntax.
- Defaults to t."
+ Defaults to t.
+- `:read-one'
+ Read a single form. Defaults to false: parse the complete input."
(if (stringp (car string-and-options))
(with-temp-buffer
(insert (car string-and-options))
diff --git a/test/parseclj-test.el b/test/parseclj-test.el
index a25d2e4e3b..a60ad9407a 100644
--- a/test/parseclj-test.el
+++ b/test/parseclj-test.el
@@ -319,6 +319,23 @@
(new-stack (nthcdr (+ (length top-value) (length opening-token))
stack)))
top-value)))
+(ert-deftest parseclj---read-one-test ()
+ (equal (parseclj-parse-clojure "(+ 1 1) foo bar" :read-one t)
+ '((:node-type . :list)
+ (:position . 1)
+ (:children ((:node-type . :symbol)
+ (:position . 2)
+ (:form . "+")
+ (:value . +))
+ ((:node-type . :number)
+ (:position . 4)
+ (:form . "1")
+ (:value . 1))
+ ((:node-type . :number)
+ (:position . 6)
+ (:form . "1")
+ (:value . 1))))))
+
(provide 'parseclj-test)
;;; parseclj-test.el ends here
