From: Robert Klemme <shortcutter@...>
Date: 2007-07-17T23:12:30+09:00
Subject: Re: Are we cool? method_missing in enumerator

2007/7/17, Trans <transfire@gmail.com>:
> Can anyone demonstrate problems with the following?
>
>   # Adds immediate elementwise ability to Enumerator.
>   # Any non-enumeration method is passed on to each.
>   #
>   #   [1,2,3].to_enum(:map) + 3
>   #   => [4,5,6]
>   #
>   # Note there may be a few essential methods this can not
>   # be used on, such as #object_id.
>
>   class Enumerable::Enumerator
>     def method_missing(sym,*args,&blk)
>       each{ |x| x.send(sym,*args,&blk) }
>     end
>   end
>
> I like the simplicity of this and would rather use it than add an
> another class layer, but I need to be sure I'm not overlooking any
> potential dangers with doing so.

Cool indeed!  The only thing that comes to mind at the moment is a
certain inconsistency that this creates: all methods implemented in
the Enumerator are methods operating on the collection while methods
invoked by your extension are invoked per instance in the collection.
I am not sure whether that actually disqualifies the change as a std
lib change...

Btw, your sample would be equally simple by doing [1,2,3].map {|x|
x+3} - it's even less typing. ;-)

Kind regards

robert