From: Christoph Rippel <crippel@...>
Date: 2001-01-08T08:11:00+09:00
Subject: [ruby-talk:8797] Re: No :<, :>, etc. methods for Array

> -----Original Message-----
> From: Brian F. Feldman [mailto:green@FreeBSD.org]
> Sent: Sunday, January 07, 2001 11:46 AM
> To: ruby-talk ML
> Subject: [ruby-talk:8782] Re: No :<, :>, etc. methods for Array
> Except that I don't really ever see the need for the inject functionality 
> itself.  A general sum method wouldn't prevent an inject method from being 
> created, and I feel it's much more generally important (if it were in 
> Enumerable, it feels natural next to min and max).
> 
> I know you can define sum in terms of inject, but what is the point of 
> having inject if people are just going to use it to create sum?
Obviously,

your question is ``only'' a matter of taste. Personally I already 
dislike the inclusion of max,min and sort in the Array class  instead 
of creating a proper ``array > sortable array > numeric array'' class 
hierarchy. 


My secret wish for 1.7 would be the creation of a parallel (for 
legacy reasons) more fine grained collection class hierarchy instead 
of the current everything is either an ``Array or Hash'' strategy,
in which Arrays can take on the roles of Sets, MultiSets, Numerical  
Arrays, Stacks, etc. . Introducing specialized collection classes
could make Ruby more efficient, clearly expresses the indent of usage
and could provide a definite answer on whether a general #sum method 
should be included or what the proper definition of the intersection 
of arrays should be ... .

> -----Original Message-----
> From: gotoken@hanare00.math.sci.hokudai.ac.jp
> [mailto:gotoken@hanare00.math.sci.hokudai.ac.jp]On Behalf Of GOTO
> Kentaro
>   def sum(if_empty = 0)  # Is the integer zero suitable?
An alternative would be the introduction of a ZERO and ONE constants 
in the Numeric class (possibly overridden in subclasses)? 

Christoph