From: Austin Ziegler <halostatue@...>
Date: 2005-07-08T07:35:12+09:00
Subject: Re: Inheriting Array and slice() behaviour

On 7/7/05, William Morgan <wmorgan-ruby-talk@masanjin.net> wrote:
> Excerpts from Pit Capitain's mail of  7 Jul 2005 (EDT):
> > The LSP has been mentioned before in this thread. According to that
> > principle, if someone creates a subclass of Array, you should be able
> > to use the subclass like the original Array class. Array has a well
> > defined #initialize method that can take zero arguments. So should the
> > subclass, otherwise you're breaking the LSP. In other words, it's
> > perfectly legal to call self.class.new in #slice. If Expression can't
> > provide an #initialize method without arguments, it shouldn't be a
> > subclass of Array.
> So you're suggesting that #initialize be called (automatically) by
> Array#slice, with no arguments? And, presumably, an ArgumentError raised
> if it has required arguments?

No, from a design level, Expression isn't an Array if it doesn't
accept #initialize with no arguments.

-austin
-- 
Austin Ziegler * halostatue@gmail.com
               * Alternate: austin@halostatue.ca