Re: Using VC for change descriptions

[Alfred M. Szmidt]

Here is an example where diffs simply do not work, when you modify the
top of a function.  It will show the function that precedes it as the
one being modified.  

If you add multiple functions, or remove them, there is no indication
in the diff that you did so other than having to scroll through the
whole thing.

If you rename a function, the diff will also be wrong .. there will be
no mention of the function you removed in the hunk, or it will mention
the wrong function similar for adding one.

@@ -1512,13 +1512,15 @@ face-spec-set-match-display
     match))
 
 
-(defun face-spec-choose (spec &optional frame)
-  "Choose the proper attributes for FRAME, out of SPEC.
-If SPEC is nil, return nil."
+(defun face-spec-choose (spec &optional frame no-match-retval)
+  "Return the proper attributes for FRAME, out of SPEC.
+
+If no match is found or SPEC is nil, return nil, unless NO-MATCH-RETVAL
+is given, in which case return its value instead."