Forum: Ruby %w{tomato cheese ham pineapple}.join(', ', ' and ')

Announcement (2017-05-07): www.ruby-forum.com is now read-only since I unfortunately do not have the time to support and maintain the forum any more. Please see rubyonrails.org/community and ruby-lang.org/en/community for other Rails- und Ruby-related community platforms.
Benjohn B. (Guest)
on 2006-04-01 21:20
(Received via mailing list)
=> 'tomato, cheese, ham and pineapple'

Is something I'd like to be able to do, and I almost thought it's be
part of the standard. Is there already a standard way of getting that
(facets, perhaps?)? Any chance it'll make it in to the standard
Enumerable?

Cheers,
	Benj
James G. (Guest)
on 2006-04-01 21:29
(Received via mailing list)
On Apr 1, 2006, at 11:20 AM, Benjohn B. wrote:

> => 'tomato, cheese, ham and pineapple'
>
> Is something I'd like to be able to do, and I almost thought it's
> be part of the standard. Is there already a standard way of getting
> that (facets, perhaps?)? Any chance it'll make it in to the
> standard Enumerable?

 >> list = %w{tomato cheese ham pineapple}
=> ["tomato", "cheese", "ham", "pineapple"]
 >> [list[0..-2].join(", "), list[-1]].join(", and ")
=> "tomato, cheese, ham, and pineapple"

Hope that helps.

James Edward G. II
Cameron McBride (Guest)
on 2006-04-02 00:33
(Received via mailing list)
On 4/1/06, Benjohn B. <removed_email_address@domain.invalid> wrote:
> => 'tomato, cheese, ham and pineapple'
>
> Is something I'd like to be able to do, and I almost thought it's be
> part of the standard. Is there already a standard way of getting that
> (facets, perhaps?)? Any chance it'll make it in to the standard
> Enumerable?

another alternative:

  %w{tomato cheese ham pineapple}.join(', ').sub(/, (\S+)$/,' and \1')

(I'm not Mr. Grammar, but I usually remove the last comma before the
"and")

Cameron
Mike S. (Guest)
on 2006-04-02 02:38
(Received via mailing list)
On 1-Apr-06, at 3:32 PM, Cameron McBride wrote:

>   %w{tomato cheese ham pineapple}.join(', ').sub(/, (\S+)$/,' and \1')
>
> (I'm not Mr. Grammar, but I usually remove the last comma before
> the "and")

The Oxford comma is useful and acceptable.  If there is any ambiguity
in the list then the comma can be most useful.  To lift from http://
www.worldwidewords.org/qa/qa-oxf1.htm:

> The argument for using it is that it reduces the risk of ambiguity.
> For example, if you were to write ?He studied Roman history,
> international politics and economics? it is not obvious whether
> international refers only to politics or also to economics. Putting
> the serial comma in removes that doubt. In practice, an alert
> writer will spot the potential problem and can often write around it.
>
> Perhaps the best argument for the serial comma is that apocryphal
> book dedication: ?To my parents, Ayn Rand and God?.

Mike


--

Mike S. <removed_email_address@domain.invalid>
http://www.stok.ca/~mike/

The "`Stok' disclaimers" apply.
David V. (Guest)
on 2006-04-02 04:29
(Received via mailing list)
DÅ?a Sobota 01 Apríl 2006 19:20 Benjohn B. napísal:
> => 'tomato, cheese, ham and pineapple'
>
> Is something I'd like to be able to do, and I almost thought it's be
> part of the standard. Is there already a standard way of getting that
> (facets, perhaps?)? Any chance it'll make it in to the standard
> Enumerable?
>
> Cheers,
> 	Benj

A little late, but in spirit of when the thread started: I'd get the
pizza
delivered ;)

David V.
Benjohn B. (Guest)
on 2006-04-02 04:32
(Received via mailing list)
On 1 Apr 2006, at 18:27, James Edward G. II wrote:

> => ["tomato", "cheese", "ham", "pineapple"]
> >> [list[0..-2].join(", "), list[-1]].join(", and ")
> => "tomato, cheese, ham, and pineapple"
>
> Hope that helps.
>
> James Edward G. II

! :) Thanks!

Argh, and it almost works in the edge cases, except for when there's
0 or 1 item in the list.

a = [1]
=> [1]
irb(main):030:0> [a[0..-2].join(', '), a[-1]].join(' and ')
=> " and 1"
irb(main):031:0> a = []
=> []
irb(main):032:0> [a[0..-2].join(', '), a[-1]].join(' and ')
=> " and "

When I was looking at this earlier, I found that..

def a_function(arg1, arg2 = arg1)
	puts arg1, arg2
end

...worked as I'd expect, and was surprised that join didn't take an
optional second argument to be the separator between the last two items.

Cheers,
	Benj
Benjohn B. (Guest)
on 2006-04-02 04:41
(Received via mailing list)
On 1 Apr 2006, at 21:32, Cameron McBride wrote:

> .join(', ').sub(/, (\S+)$/,' and \1')

:) Groovy - and it works for the edge cases too...

irb(main):033:0> a=[1,2,3]
=> [1, 2, 3]
irb(main):034:0> a.join(', ').sub(/, (\S+)$/,' and \1')
=> "1, 2 and 3"
irb(main):035:0> a=[1,2]
=> [1, 2]
irb(main):036:0> a.join(', ').sub(/, (\S+)$/,' and \1')
=> "1 and 2"
irb(main):037:0> a=[1]
=> [1]
irb(main):038:0> a.join(', ').sub(/, (\S+)$/,' and \1')
=> "1"
irb(main):039:0> a=[]
=> []
irb(main):040:0> a.join(', ').sub(/, (\S+)$/,' and \1')
=> ""

Thanks.

It still seems like a nice one to have in the standard, to me.

Cheers,
	B
Benjohn B. (Guest)
on 2006-04-02 04:44
(Received via mailing list)
On 2 Apr 2006, at 01:26, David V. wrote:

>
> A little late, but in spirit of when the thread started: I'd get
> the pizza
> delivered ;)

Good timing - I'm munchy.
Trans (Guest)
on 2006-04-02 04:44
(Received via mailing list)
That's an interesting idea. Perhaps an options hash though in case
anyone thinks of alternatives:

  join( ', ', :last => ' and ')

T.
Benjohn B. (Guest)
on 2006-04-02 04:50
(Received via mailing list)
On 2 Apr 2006, at 01:40, Benjohn B. wrote:
> It still seems like a nice one to have in the standard, to me.

Is there somewhere for suggestion new features? I'm sure I remember
seeing that, but I'm having trouble tracking it down.

Cheers,
	Ben
unknown (Guest)
on 2006-04-02 05:00
(Received via mailing list)
Hi --

On Sun, 2 Apr 2006, Benjohn B. wrote:

>
> On 2 Apr 2006, at 01:40, Benjohn B. wrote:
>> It still seems like a nice one to have in the standard, to me.
>
> Is there somewhere for suggestion new features? I'm sure I remember seeing
> that, but I'm having trouble tracking it down.

Once you've really determined that you can make a case for it, you can
prepare an RCR (Ruby Change Request) and post it to
http://www.rcrchive.net (now running on my new server; if the name
resolves to the old one, wait a day or two).


David

--
David A. Black (removed_email_address@domain.invalid)
Ruby Power and Light, LLC (http://www.rubypowerandlight.com)

"Ruby for Rails" chapters now available
from Manning Early Access Program! http://www.manning.com/books/black
Logan C. (Guest)
on 2006-04-02 05:24
(Received via mailing list)
On Apr 1, 2006, at 7:32 PM, Benjohn B. wrote:

>>> the standard Enumerable?
> ! :) Thanks!
> irb(main):032:0> [a[0..-2].join(', '), a[-1]].join(' and ')
> items.
>
> Cheers,
> 	Benj
>
>

This works in all the edge cases also, but its a bit verbose:
class Array
   def multi_join(*args)
     if args.empty?
       join
     elsif args.length == 1
       join(args[0])
     else
       accum = ""
       normal = args[0]
       last = args[1]
       index_of_second_to_last_item = length - 2
       index_of_last_item = length - 1
       each_with_index do |item, count|
         accum << item.to_s
         if count == index_of_last_item
           break
         elsif count == index_of_second_to_last_item
           accum << last
         else
           accum << normal
         end
       end
       accum
     end
   end
end
Benjohn B. (Guest)
on 2006-04-02 11:28
(Received via mailing list)
On 2 Apr 2006, at 01:58, removed_email_address@domain.invalid wrote:

>
> Once you've really determined that you can make a case for it, you can
> prepare an RCR (Ruby Change Request) and post it to
> http://www.rcrchive.net (now running on my new server; if the name
> resolves to the old one, wait a day or two).

Thank you, I'll do that. I was wracking my brains trying to remember
that last night, and all I could come up with to Google was feature
request.

Cheers,
	Benjohn
joey__ (Guest)
on 2006-04-02 22:52
class Array
def join_sentence
          case length
            when 1
              self[0]
            when 2
              "#{self[0]} and #{self[1]}"
            else
              "#{self[0...-1].join(', ')} and #{self[-1]}"
          end
end
end
Brian B. (Guest)
on 2006-04-03 16:04
(Received via mailing list)
One more tweak for the empty array if "" makes sense.

class Array
  def join_sentence
    case length
    when 0: ""
    when 1: self[0]
    else [self[0..-2].join(", "), self[-1]].join(" and ")
    end
  end
end
This topic is locked and can not be replied to.