Prepare for any keys in blame listings.

src/listing.scm

@@ -140,7 +140,8 @@
 		 (#:context-post ctx-post "")
 		 (#:highlight-pre hl-pre a:error)
 		 (#:highlight-post hl-post a:default)
-		 (#:context context 3))
+		 (#:context context 3)
+		 (#:keys keys '(number line comment)))
    (let loop ((lines lines)
 	      (number 1)
 	      (printed-something #f)
@@ -179,20 +180,27 @@
 		       (add1 number)
 		       #t
 		       #t
-		       (cons (list (format "\t~A~A. ~A" pre-str number post-str)
-				   (format "~A~A~A"
-					   pre-str
-					   (if (ldict? line)
-					       (ldict-ref line 'line)
-					       line)
-					   post-str)
-				   (if comment
-				       (format "~A  # <<< ~A~A"
+		       (cons (map (lambda (key)
+				    (case key
+				      ((number)
+				       (format "\t~A~A. ~A" pre-str number post-str))
+				      ((line)
+				       (format "~A~A~A"
 					       pre-str
-					       comment
-					       post-str)
-				       "")
-				   )
+					       (if (ldict? line)
+						   (ldict-ref line 'line)
+						   line)
+					       post-str))
+				      ((comment)
+				       (if comment
+					   (format "~A  # <<< ~A~A"
+						   pre-str
+						   comment
+						   post-str)
+					   ""))
+				      (else
+				       "xxx")))
+				  keys)
 			     rtbl)))
 	       (loop (cdr lines)
 		     (+ number 1)