A little bit of code golfing

1 files changed, 14 insertions, 21 deletions

diff --git a/chess-ply.el b/chess-ply.el
index dfae21f..66df7f3 100644
--- a/chess-ply.el
+++ b/chess-ply.el
@@ -177,26 +177,21 @@
   (list position))
 
 
-(defvar promotion-options
-  '(queen rook bishop knight))
+(defconst promotion-options
+  '((queen  ?Q ?q)
+    (rook   ?R ?r)
+    (bishop ?B ?b)
+    (knight ?N ?n)))
 
 (defun ask-promotion (white)
-  (let ((p (ido-completing-read "Symbol? " (mapcar #'symbol-name promotion-options))))
-    (cond ((string= "queen" p)
-           (if white ?Q ?q))
-
-          ((string= "rook" p)
-           (if white ?R ?r))
-
-          ((string= "bishop" p)
-           (if white ?B ?b))
-
-          ((string= "knight" p)
-           (if white ?N ?n))
-
-          ;; Promote to queen as fallback
-          (t (if white ?Q ?q)))))
-
+  (nth (if white 1 2)
+       (assoc (intern-soft
+               (or (completing-read
+                    "Symbol? "
+                    (mapcar (lambda (x) (symbol-name (car x)))
+                            promotion-options))
+                   "queen"))
+              promotion-options)))
 
 (defun chess-ply-create (position &optional valid-p &rest changes)
   "Create a ply from the given POSITION by applying the supplied CHANGES.
@@ -246,9 +241,7 @@ maneuver."
 			 (= (if color 0 7)
 			    (chess-index-rank (cadr changes))))
                 (let ((promo (ask-promotion color)))
-                  (setq changes
-                        (append changes (list :promote promo)))
-                  
+                  (nconc changes (list :promote promo))
                   (setq ply (cons position changes))))
 
 	      ;; is this an en-passant capture?