where is 'ev' defined?



Hello,
 Where is the builtin function 'ev' defined? 

Actually, this brings up a suggestion.   In the help files -e.g. the 
information obtained using the '?' command, it would be extermely useful 
to add a statement giving the source file for the indicated command (or 
perhaps a list of associated source files)

For one thing, it would eliminate most of these kinds of messages.

TIA,
 -sen