branch: externals/m-buffer
commit ea281db21af0dd48ba08f7f8e0cd2902acdf5a96
Author: Phillip Lord <[email protected]>
Commit: Phillip Lord <[email protected]>
New function: m-buffer-partition-by-marker.
---
m-buffer.el | 32 ++++++++++++++++++++++++++++++++
test/m-buffer-test.el | 14 ++++++++++++++
2 files changed, 46 insertions(+)
diff --git a/m-buffer.el b/m-buffer.el
index 21e8efae60..948033282f 100644
--- a/m-buffer.el
+++ b/m-buffer.el
@@ -405,6 +405,8 @@ function. See `m-buffer-nil-marker' for details."
;; ** Match Utility and Predicates
+;; *** Subtraction
+
;; Some predicates and the ability to subtract to lists of matches from each
;; other. This makes up for limitations in Emacs regexp which can't do "match x
;; but not y".
@@ -492,6 +494,36 @@ in M."
matches))
;; #+end_src
+
+;; *** Partition
+
+;; Partition one set of markers by another. This is useful for finding matched
+;; pairs of markers.
+
+;; #+begin_src emacs-lisp
+(defun m-buffer--split-partition (partition)
+ (let ((current nil))
+ (lambda (n)
+ (when
+ (and partition
+ (<= (car partition) n))
+ (setq current (car partition))
+ (setq partition (-drop 1 partition)))
+ current)))
+
+(defun m-buffer-partition-by-marker (list partition)
+ "Given LIST of markers, split at markers in PARTITION.
+Returns a list of lists. The first element of each list is nil or
+the marker from PARTITION. The rest of the elements are those
+elements in LIST which are at the same position or later in the
+buffer than the element from PARTITION, but before the next
+element from PARTITION.
+
+Both LIST and PARTITION must be sorted."
+ (-group-by (m-buffer--split-partition partition) list))
+;; #+end_src
+
+
;; ** Marker manipulation functions
;; These functions do things to markers rather than the areas of the buffers
diff --git a/test/m-buffer-test.el b/test/m-buffer-test.el
index f81763fdef..afe828374b 100644
--- a/test/m-buffer-test.el
+++ b/test/m-buffer-test.el
@@ -407,4 +407,18 @@ should not have moved."
(m-buffer-match-word
(current-buffer) :regexp "notword")))
+
+(ert-deftest partition-by-markers ()
+ (should
+ (equal
+ '((nil 1)
+ (2 2 3 4)
+ (5 5 6 7)
+ (8 8 9))
+ (m-buffer-partition-by-marker
+ '(1 2 3 4 5 6 7 8 9)
+ '(2 5 8)
+ ))))
+
+
;;; m-buffer-test.el ends here
