- BeginEdit()). If it isn't, it just returns @false, otherwise it fills
- @a newval with the representation of the new value in the string form,
- if necessary saves it using its real type internally, and returns @true.
+ BeginEdit()). If it isn't, it just returns @false, otherwise it must do
+ the following:
+ # Save the new value internally so that ApplyEdit() could apply it.
+ # Fill @a newval (which is never @NULL) with the string
+ representation of the new value.
+ # Return @true
+
+ Notice that it must @em not modify the grid as the change could still
+ be vetoed.