From: Benjohn Barnes <benjohn@...>
Date: 2006-04-02T09:32:28+09:00
Subject: Re: %w{tomato cheese ham pineapple}.join(', ', ' and ')


On 1 Apr 2006, at 18:27, James Edward Gray II wrote:

> On Apr 1, 2006, at 11:20 AM, Benjohn Barnes 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 Gray 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