From: Dan Doel <djd15@...>
Date: 2003-08-12T06:27:05+09:00
Subject: Re: Ruby and OOP-design (question of an old "procedural person" ;)

Meino Christian Cramer wrote:

>Hi, :)
>
> THANK YOU VERY MUCH FOR THE IMMENS RESPONSE TO MY QUESTION!
>
> I am very happy to be on this very communicative list :o) !
>
> Since I am at the very very beginning of Ruby-Programming please
> understand, that I only understand the smallest part of the
> discussion...
>
> In the meantime I git a sorted list of "my" shortwave transmitters.
>
> I did:
>
>       @list.push( [freq, stat, time, days, lang, graf, targ, 
>                   loca, powr, azim,rema, stau, modu, na, ca, 
>                   sa, eu, af, me, as, au, pa, cira, coco, coun, 
>                   long, lati, loco, regi, stn , prst, prog] )
>
> for each input line.
>
> Then I did a 
>
>	   @list.sort_by { |item| [item[0], item[2] ] }
>
> and it works smooth and fast as a ligthning.
>
> The above expressions sorts the broadcasters first on frequency then
> on on-air time.
>
> Then I thought of a list first sorted by time and then by frequency
> and wrote 
>
>	   @list.sort_by { |item| [item[2], item[0] ] }
>
> and astonishly Ruby quaks ;) with :
>
> swlist:62:in `sort_by': comparison of Array with Array failed (ArgumentError)
>        from swlist:62
>
> ("swlist" is the name of my ruby-script) 
> 
> I dont understand that...
>
> I am sure that the bug is sitting in front of my monitor...but...
>
> What is it what I did so badly wrong ? X)
>
> Thank you very much for any help in advance !
>
> Keep being Ruby!
> Meino
>
>  
>
Maybe there's a problem with one of the times?  Since the first sort_by 
would look at item[0] first
and only item[2] if both item[0]'s are the same (I think), it might skip 
over the problem time value,
while the second wouldn't be able to;

Maybe try printing out all the item[2] values and looking for something 
fishy there? Just a thought.

- Dan