From: ara.t.howard@...
Date: 2006-03-15T00:38:45+09:00
Subject: Re: how to introduce reference objects into ruby

On Tue, 14 Mar 2006, Geert Fannes wrote:

> In Ruby, there's the []= and [] operators which you can define together.
> The []= can play both the role of subscripting and assignment without
> needing any intermediate references. Also, Ruby's subscript operator can
>
> take any number of arguments. The right-handed value is always the last
> in
> the list of args.
>
> class MyMatrix
>  ...
>  def []=(i,j,value)
>    @rows[i][j]=value
>    @columns[i][j]=value
>  end
> end
>
> mm=MyMatrix.new
> mm[3,5] = 42
>
> Indeed, the only drawback is that I have to keep the row and column-wise
> elements synchronized, e.g., after an addition or something. For a
> matrix with equal row and column sizes, this would mean a duplication of
> the needed operations if a reference object existed. But when row "i" is
> much longer than column "j", I would rather only lookup and modify the
> element (i,j) via the columns, since the Hash llokup for the row will
> take much longer.
>
> Greetings,
> Geert.

this seems like so much work - why not simply use narray - it does nearly all
this already?

-a
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