OK, first I just *have* to ask:  Do you have a copy of Programming Ruby?

No?  Get the first edition here: http://www.ruby-doc.org/docs/ 
ProgrammingRuby/

keep reading...!

On Jun 26, 2006, at 1:27 PM, Dark Ambient wrote:

> Alright, if there are any people remaining that have some patience to
> repeat I'm running into the same problem again. And for now I really
> want to stick to while,because now it's a real sticking point for me.
> If I do nothing else in Ruby, mastering the while statement is a
> must.:)
>
> So here I've created a method.  See inline for why I think it  
> should work.
>
> #sort is the parameter for the alpha method
> def alpha sort
>
> #setting up my arrays
>  s_words = []
>  u_words = []
>
> #assign a blank string to sort to start things off
>  sort = ' '
Why are you using sort as a parameter and then overwriting it here?!
>
> # what I'm trying to say here is that if sort remains empty  
> continue the loop
> while sort == ' '
> # to prompt the user to enter something I've added the puts statement
>  puts 'Please enter a word to be sorted'
> #Now I'll assign sort to whatever the user inputs.
>  sort = gets.chomp.downcase
> #Now I want to put the string into the array.
>  u_words.push['sort']

u_words << sort

you don't want 'sort' as that's a string with s, o, r, and t -- you  
want the value of the variable sort (which would be better named  
something like: word)


> #I haven't thought it completely through but I'll probably want to
> give the user a
> #surrender word to stop the loop.  Still I think at this point it
> should loop at least
> #once.  Sadly, it does not, so either I'm thick or this is a hard
> concept for me.  #Polymorphism seems easier to grasp right now

perhaps an empty word?

>  end
> end
>
> TIA
> Stuart

instead of s_words, just use u_words.sort

And while I'm at it, perhaps the method should be called  
"get_sorted_word_list" or something else a bit more descriptive that  
simply "alpha".

-Rob

Rob Biedenharn		http://agileconsultingllc.com
Rob / AgileConsultingLLC.com

> On 6/26/06, Robert Dober <robert.dober / gmail.com> wrote:
>>
>>
>>
>> On 6/26/06, Dark Ambient <sambient / gmail.com> wrote:
>> > Robert,
>> >
>> > Thank you for a great explanation. I have a question or two and  
>> might
>> > have some more later :).  The program is an assignment in a book
>> > "learn to program" which uses Ruby but is pretty much for  
>> beginners.
>> > While I've seen some of the of the other condition testers,  
>> (when, do,
>> > case, etc) the author sticks to the real basics, while, if, else  
>> and
>> > elsif.   The author did write the program out, somewhat verbose and
>> > asked that it be re-written.  Suprisingly, he said while he DOES  
>> NOT
>> > like to use "return", he might be forgiving if it was used in the
>>
>>
>> This is a very extreme point of view, like when I learnt Pascal in
>> university.
>>
>> > re-write.  Admitedly, your code is far cleaner and more to Matz's
>> > style of Ruby being almost like pseudo-code.
>> > So, question 1 - "loop do" seems like a great alternative to  
>> "while"
>>
>>
>> No loop do ... end  or loop { } is the aequivaelent to
>>      while true do    or while(true){ }
>> it is an endless loop.
>>
>> > but could it be subsituted all the time when a loop is  
>> required ?  or
>> > are there times when while has some unique ways of doing things ?
>> >
>> > You wrote:
>> > "surprisingly the example you chose, which is needed> about  
>> everywhere is
>> > not the easiest to implement".
>>
>>
>> > Question 2 - I'm not sure how to take this statement.  To me in the
>> > context of programming it seems like a pretty basic function
>> > regardless of how one may master it but interested in why you chose
>> > the words you did ?
>>
>>
>> Because of the need to return from the middle of the loop
>>
>> > Look forward to your responses.
>> >
>> > Thank you again!
>> > Stuart
>>
>>
>> H''s been a pleasure.
>> Cheers
>> Robert
>>
>> > On 6/26/06, Robert Dober <robert.dober / gmail.com> wrote:
>> > > Hi ambient
>> > >
>> > > I will answer this off-list not because it was a bad thing of  
>> you to
>> answer
>> > > on list but just because you were unlucky with the anwsers ;)
>> > >
>> > > First I will give you the code
>> > > def ask question
>> > >      loop do  ### this loops forever, and that's what we need  
>> because of
>> the
>> > > loosers ;)
>> > >
>> > >          puts question
>> > >          case gets.chomp.downcase
>> > >              when "yes"
>> > >                 return true
>> > >              when "no"
>> > >                 return false
>> > >              else
>> > >                 puts "Please kindly reply with \"yes\" or \"no\"
>> > >         end
>> > >     end
>> > > end
>> > >
>> > > Now some explanations, the most important trick is to write  
>> your code as
>> > > simple as possible, surprisingly the example you chose, which  
>> is needed
>> > > about everywhere is
>> > > not the easiest to implement, but local exits (in our case the  
>> "return"
>> can
>> > > be very helpful).
>> > >
>> > > So what did you want to do?
>> > > Ask the user a question
>> > > get a reply
>> > > return true or false if the reply is syntactically correct
>> > > Insult the looser ;) in any other case and do it again
>> > >
>> > > As there is no looping construct which tests the looping  
>> condition after
>> the
>> > > first run of the loop body it is *normal* that your code gut  
>> clumpsy.
>> The
>> > > endless
>> > > loop do
>> > > end
>> > > or
>> > > loop {
>> > > }
>> > >
>> > > often helps to write clearer code, do not forget to break or  
>> return from
>> > > these loops though!!!
>> > >
>> > > In our case we want the method to return true or false anyway  
>> as soon as
>> the
>> > > input
>> > > is correct, so we kill to birds with one stone.
>> > >
>> > > The pseudo code above can be translated as follows
>> > >
>> > > loop do   #### preparing for the potential need to reanswer  
>> the question
>> ;)
>> > >      puts question
>> > >      case gets.chomp.downcase  ### examine the reply
>> > >         ### return true or false if the code is synt. correct
>> > >          when "yes"  ### greatinput is correct we return the
>> corresponding
>> > > value
>> > >              return true  ### returning from the method gets  
>> us out of
>> the
>> > > loop to :))
>> > >          when "no"  ### as above
>> > >              return false
>> > >         else ### Now we get to the insult part and loop back  
>> to the
>> question
>> > >             puts "Please kindly reply with \"yes\" or \"no\""
>> > >     end # case
>> > > end # loop
>> > >
>> > > Feel free 2 ask any more questions
>> > > Cheers
>> > > Robert
>> > >
>> >
>>
>>
>>
>>
>> --
>> Deux choses sont infinies : l'univers et la bóŐise humaine ; en ce  
>> qui
>> concerne l'univers, je n'en ai pas acquis la certitude absolue.
>>
>> - Albert Einstein
>