From: RoRNoob <rornoob@...>
Date: 2008-04-17T07:00:20+09:00
Subject: Re: Noob Questions [arrays]

On Apr 16, 2:49 pm, Justin Collins <justincoll...@ucla.edu> wrote:
> RoRNoob wrote:
> > On Apr 16, 9:55 am, RoRNoob <rorn...@gmail.com> wrote:
>
> >> On Apr 16, 3:25 am, Ron Fox <f...@nscl.msu.edu> wrote:
>
> >>> Approach it as follows;
> >>> 1. A loop that is not a .each loop that reads in user input
> >>>     until the input is an empty line (that is size 0 after being chomped)
> >>> 2. Then sort thearray.
> >>> 3. Then a .each iteration through thearrayto output the contents.
>
> >>> RF
>
> >>> RoRNoob wrote:
>
> >>>> Be warned - I'm new to Ruby and programming in general, so I'm sure
> >>>> this will be a trivial question for most of you.
>
> >>>> I'm currently working through the exercises in the book Learn to
> >>>> Program by Chris Pine. At the end of each chapter Chris has a little
> >>>> programming problem that the reader is asked to solve. I've been able
> >>>> to follow along just fine up until tonight.
>
> >>>> The problem in question is at the end of Chapter 8 (Arrays and
> >>>> Iterators): I have to write a program that asks the user to type in as
> >>>> many words as they want (one word per line, continuing until they just
> >>>> press Enter on an empty line) and then repeat the words back to them
> >>>> in alphabetical order.
>
> >>>> The program lives in a .rb file and is executed and ran from the
> >>>> terminal.
>
> >>>> Here is my code:
>
> >>>> alphalist = []
> >>>> alphalist.each do |item|
> >>>>   puts 'type words one at a time and I will alphabetize them for you.'
> >>>>   alphalist.pushgets.chomp
> >>>> end
> >>>> puts alphalist.sort
>
> >>>> When I run the .rb file, nothing happens. Any help is appreciated!
>
> >> Cool - I will give that a try - thanks for your time everyone!
>
> > OK progress:
>
> > alphalist = ['']
> > input = ''
>
> > while input != 'bye'
> >   puts 'type words one at a time and I will alphabetize them for you.'
> >   input = gets.chomp
> >   if input != 'bye'
> >     alphalist.push input
> >   end
> > end
>
> > puts alphalist.sort
>
> > -----
>
> > My problem is that I can't figure out how to make it exit the loop if
> > the user submits a 0 length string. The only way I've been able to get
> > it to work is to watch for 'bye' - which I like better than the empty
> > string, but the problem from the book calls for an empty string loop
> > exit
>
> I suspect your difficulty comes from the fact that you are setting input
> to the empty string before entering the while loop. One approach would
> be to start off with input as something else, like nil, then doing while
> input != ""
>
> -Justin

Solved - Thanks for the suggestion Justin. For any other noobs - here
is the solution:

alphalist = ['']
input = nil

while input != ""
  puts 'type words one at a time and I will alphabetize them for you.'
  input = gets.chomp
  alphalist.push input
end

puts alphalist.sort

Cheers!