From: w_a_x_man <w_a_x_man@...>
Date: 2009-12-11T12:05:09+09:00
Subject: Re: human-readable listing of array elements

On Dec 10, 8:36 am, Robert Klemme <shortcut...@googlemail.com> wrote:
> 2009/12/10 Aldric Giacomoni <ald...@trevoke.net>:
>
> > This took me less than a minute to write, but I don't know if it's as
> > elegant as it could be. Are there more "Ruby-like ways(tm)" to write
> > this?
>
> > def stringify array
> >  return array[0] if array.size == 1
> >  string = ""
> >  array.each_with_index do |element, index|
> >    case index
> >      when array.size - 1 # last item
> >        string += " and #{element}"
> >      when 0
> >        string += "#{element}"
> >      else
> >        string += ", #{element}"
> >    end
> >  end
> >  string
> > end
>
> By using String#<< your code will become more efficient because you do
> not create new String objects all the time.
>
> For the fun of it here are two other solutions:
>
> irb(main):026:0> def stringify array
> irb(main):027:1>   lead = array.slice 0...-1
> irb(main):028:1>   lead.empty? ? array.last.to_s : [lead.join(", "),
> array.last].join(" and ")
> irb(main):029:1> end
> => nil
> irb(main):031:0> stringify []
> => ""
> irb(main):032:0> stringify %w{foo}
> => "foo"
> irb(main):033:0> stringify %w{foo bar}
> => "foo and bar"
> irb(main):034:0> stringify %w{foo bar baz}
> => "foo, bar and baz"
>
> irb(main):039:0> def stringify array
> irb(main):040:1>   tail = array.slice -2..-1
> irb(main):041:1>   tail ? (array.slice(0...-2) << tail.join(" and
> ")).join(", ") : array.first.to_s
> irb(main):042:1> end
>
> irb(main):048:0> stringify []
> => ""
> irb(main):045:0> stringify %w{foo}
> => "foo"
> irb(main):046:0> stringify %w{foo bar}
> => "foo and bar"
> irb(main):047:0> stringify %w{foo bar baz}
> => "foo, bar and baz"
>
> Note, I don't claim that this is necessarily more rubyish. :-)
>
> Kind regards
>
> robert
>
> --
> remember.guy do |as, often| as.you_can - without endhttp://blog.rubybestpractices.com/

Sometimes it's fun to avoid using conditionals (including
"... ? ... : ...")
when programming.


def to_string ary
  a = ary.dup
  a.push( a.pop(2).join " and " ).join ", "
end