[PATCH] do not use mapcar* for transposing tables

[PATCH] do not use mapcar* for transposing tables

[Achim Gratz]

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I've recently stumbled over a mapcar* compiled into Org for transposing
tables.  This is a function from cl / cl-lib and should not be used at
runtime.  Since we can make some simplifying assumptions about the data
we'll have to deal with, re-implmenting the two uses with plain mapcar
was (relatively) painless.


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From 8941eb1f7ed2a7f1164a92a957a53560127cc26f Mon Sep 17 00:00:00 2001
From: Achim Gratz <Stromeko@Stromeko.DE>
Date: Fri, 21 Jun 2013 22:37:51 +0200
Subject: [PATCH] do not use mapcar* for transposing tables

* lisp/ob-core.el (org-babel-get-rownames),
  lisp/org-table.el (org-table-transpose-table-at-point): Replace the
  inadvertent use of mapcar* (from cl) by plain mapcar and direct cons
  manipulation.

The error was not caught at compilation time since both source files
require cl during compilation for using cl macros.  These were the
only uses of mapcar* in Org, but I didn't check for other cl
_functions_ (as opposed to macros, which would need to be checked if
their implementation uses cl functions).
---
 lisp/ob-core.el   | 28 ++++++++++++----------------
 lisp/org-table.el | 15 ++++++++++-----
 2 files changed, 22 insertions(+), 21 deletions(-)

diff --git a/lisp/ob-core.el b/lisp/ob-core.el
index e2cb03b..a22a696 100644
--- a/lisp/ob-core.el
+++ b/lisp/ob-core.el
@@ -1502,22 +1502,18 @@ (defun org-babel-get-colnames (table)
 (defun org-babel-get-rownames (table)
   "Return the row names of TABLE.
 Return a cons cell, the `car' of which contains the TABLE less
-colnames, and the `cdr' of which contains a list of the column
-names.  Note: this function removes any hlines in TABLE."
-  (let* ((trans (lambda (table) (apply #'mapcar* #'list table)))
-	 (width (apply 'max
-		       (mapcar (lambda (el) (if (listp el) (length el) 0)) table)))
-	 (table (funcall trans (mapcar (lambda (row)
-					 (if (not (equal row 'hline))
-					     row
-					   (setq row '())
-					   (dotimes (n width)
-					     (setq row (cons 'hline row)))
-					   row))
-				       table))))
-    (cons (mapcar (lambda (row) (if (equal (car row) 'hline) 'hline row))
-		  (funcall trans (cdr table)))
-	  (remove 'hline (car table)))))
+rownames, and the `cdr' of which contains a list of the rownames.
+Note: this function removes any hlines in TABLE."
+  (let* ((table (org-babel-del-hlines table))
+	 (rownames (funcall (lambda ()
+			      (let ((tp table))
+				(mapcar
+				 (lambda (row)
+				   (prog1
+				       (pop (car tp))
+				     (setq tp (cdr tp))))
+				 table))))))
+    (cons table rownames)))
 
 (defun org-babel-put-colnames (table colnames)
   "Add COLNAMES to TABLE if they exist."
diff --git a/lisp/org-table.el b/lisp/org-table.el
index 9468b2b..243449f 100644
--- a/lisp/org-table.el
+++ b/lisp/org-table.el
@@ -1870,11 +1870,16 @@ (defun org-table-transpose-table-at-point ()
 
 Note that horizontal lines disappeared."
   (interactive)
-  (let ((contents
-         (apply #'mapcar* #'list
-                ;; remove 'hline from list
-		(delq nil (mapcar (lambda (x) (when (listp x) x))
-				  (org-table-to-lisp))))))
+  (let* ((table (delete 'hline (org-table-to-lisp)))
+	 (contents (mapcar (lambda (p)
+			     (let ((tp table))
+			       (mapcar
+				(lambda (rown)
+				  (prog1
+				      (pop (car tp))
+				    (setq tp (cdr tp))))
+				table)))
+			   (car table))))
     (delete-region (org-table-begin) (org-table-end))
     (insert (mapconcat (lambda(x) (concat "| " (mapconcat 'identity x " | " ) "  |\n" ))
                        contents ""))
-- 
1.8.3


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Regards,
Achim.
-- 
+<[Q+ Matrix-12 WAVE#46+305 Neuron microQkb Andromeda XTk Blofeld]>+

SD adaptation for Waldorf rackAttack V1.04R1:
http://Synth.Stromeko.net/Downloads.html#WaldorfSDada

Re: [PATCH] do not use mapcar* for transposing tables

[Bastien]

Hi Achim,

Achim Gratz <Stromeko@nexgo.de> writes:

> I've recently stumbled over a mapcar* compiled into Org for transposing
> tables.  This is a function from cl / cl-lib and should not be used at
> runtime.  Since we can make some simplifying assumptions about the data
> we'll have to deal with, re-implmenting the two uses with plain mapcar
> was (relatively) painless.

Looks good, please apply in maint.

Thanks!

-- 
 Bastien

Re: [PATCH] do not use mapcar* for transposing tables

[Achim Gratz]

Bastien writes:
> Looks good, please apply in maint.

Done.


Regards,
Achim.
-- 
+<[Q+ Matrix-12 WAVE#46+305 Neuron microQkb Andromeda XTk Blofeld]>+

Waldorf MIDI Implementation & additional documentation:
http://Synth.Stromeko.net/Downloads.html#WaldorfDocs

Re: [PATCH] do not use mapcar* for transposing tables

[Bastien]

Achim Gratz <Stromeko@nexgo.de> writes:

> Bastien writes:
>> Looks good, please apply in maint.
>
> Done.

Thanks!

-- 
 Bastien