(require): Explain why CL is needed.

diff --git a/lisp/tooltip.el b/lisp/tooltip.el
index cb0fbfe29c64fc09440fb3ca27b95f001a888ad6..f8243f4a0ac3db220ee2cc45e8bef4a0b006b218 100644 (file)
--- a/lisp/tooltip.el
+++ b/lisp/tooltip.el
@@ -26,7 +26,7 @@
 
 ;;; Code:
 
-(eval-when-compile (require 'cl))
+(eval-when-compile (require 'cl)) ; for case macro
 
 \f
 ;;; Customizable settings