From: Daniel Schierbeck <daniel.schierbeck@...>
Date: 2005-10-28T23:07:05+09:00
Subject: Re: Cleaner syntax for .map (is there already a way, or ruby2 idea?)

David A. Black wrote:
> Hi --
> 
> On Fri, 28 Oct 2005, Daniel Schierbeck wrote:
> 
>> Daniel Schierbeck wrote:
>>
>>> David A. Black wrote:
>>>
>>>> I know that people.every could return
>>>> some kind of generator or enumerator, which could then be fed
>>>> "email_addr" symbolically... 
>>>
>>>
>>>
>>>
>>> module Enumerable
>>>   def every
>>>     enum, obj = self, Object.new
>>>     obj.define_method :method_missing do |name, *args|
>>>       enum.map { |element| element.send(name, *args) }
> 
> 
> If you must do this, you'd probably want each rather than map there.

Nope. I wan't it to return an array of the values returned.

   ["john", "sylvia", "sarah"].every.upcase -> ["JOHN", "SYLVIA", "SARAH"]

That's of course not a very good example. This would probably be better:

   addresses = contacts.every.email_addr

As opposed to

   addresses = contacts.collect { |contact| contact.email_addr }

But I agree that the dot syntax is bad, I was just proving that it could 
easily be done. This would be better:

   addresses = contacts.every(:email_addr)

And maybe even have a `with_every' method:

   contacts.with_every(:email_addr) do |email_addr|
     puts " - " + email_addr
   end

Which could be implemented this way

   module Enumerable
     def with_every(*args)
       each do |element|
         yield element.send(*args)
       end
     end
   end



Cheers,
Daniel