Iteration the ruby way

ruby-talk
1

Lähettäjä: Navindra Umanee <navindra@cs.mcgill.ca>
Aihe: Re: iteration the ruby way

> > I have a question about The Ruby Way. Pickaxe gives the following
> > example for using iterators in Ruby:
> >
> > a = [ "a", "b", "c" ]
> > a.each {|x| print x, " -- " }
> >
> > This outputs:
> >
> > a -- b -- c --
> >
> > But what if I want to print "a -- b -- c"? What's the proper Ruby way
> > of doing that?
>
> a = ["a","b","c"]
> puts a.join(' - ')

I guess I over-simplified. I really want to do computations based on
each element and compute my output. However, it's slightly different
for the last element. I would like to detect the last element in the
iteration.

For example:

     bottom_items.each{ |item|
        do_something_with(item[0], item[1], item[2])
  if_not_last_item_do_this
     }

Since you're not doing the same thing on all elements, these should
be conceptually correct.

  ary = ary[0..-1].each {|el| do_something el }
  do_something_else!(ary.last)

  ary.each_index {|i| do_smth(ary[i]) unless i == ary.size - 1}

Thanks,
Navin.

E

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John Wilger <johnwilger@gmail.com> wrote: