From: Todd Benson <caduceass@...>
Date: 2008-02-21T10:51:28+09:00
Subject: Re: displaying user inputed arrays

On Wed, Feb 20, 2008 at 7:39 PM, Todd Benson <caduceass@gmail.com> wrote:
> On Wed, Feb 20, 2008 at 5:36 PM, Isaac Toothyxdip <toothyxdip@gmail.com> wrote:
>  > Thanks that really shortens up my code and works but i have a couple
>  >  questions
>  >
>  >
>  >
>  >
>  >  a, n = nil
>  >  puts "Please enter 5 words"
>  >  until (a = (gets.scan /[\w'-]*/) - [""]).length == 5
>  >   puts "Please type in exactly FIVE words, thanks."
>  >  end
>  >  puts "You would like to print out which word number? (1-5)"
>  >  until (1..5).include? (n = gets.chomp.to_i)
>  >   puts "Please pick a number 1 through 5"
>  >  end
>  >  puts a[n - 1]
>  >
>  >  i under stand almost all of it (i just dont get what the - [""] does and
>
>  Try [1, 2, 3, 4] - [1, 4] to understand the methodology, - [""]
>  removes empty strings created by scan because /[\w'-]/ is not only
>  greedy, but _zero_or_more_, which means it will return empty strings
>  for characters you don't include (like spaces).
>
>
>  >  i think that means that it puts it into an array

I forgot to mention the #scan method is what creates an array.

> but the main questions
>  >  i have are why did you type a, n = nil that isnt needed
>
>  You're right.  It isn't necessary.  I thought it might be for scope reasons.
>
>
>  > and also why did
>  >  you type /[\w'-]*/) when /\w+/ works the same ... i think

I created a character class (the square brackets) that included \w and
' and - because "you're" is a word, as is "able-bodied".  Like I said,
if you use the *, you will get several empty strings in the array the
the #scan method gives you, which you would have to subtract, but you
can bypass that ugliness with using the + instead.

hope that makes some sense,
Todd