From: Sean O'Halpin <sean.ohalpin@...>
Date: 2007-04-06T23:12:51+09:00
Subject: Re: the most useful code i've written in a while

On 4/6/07, Robert Klemme <shortcutter@googlemail.com> wrote:
> On 06.04.2007 02:54, Trans wrote:
> >
> > On Apr 5, 5:34 pm, "Ara.T.Howard" <ara.t.how...@noaa.gov> wrote:
> >> harp:~ > cat errno
> >> #! /usr/bin/env ruby
> >> 256.times do |errno|
> >>    puts "#{ errno } => #{ SystemCallError.new(errno).inspect }"
> >> end
> >
> > Nice.
> >
> > Hmm... How about an inheritance tree too?
>
> robert@fussel /cygdrive/c/Temp
> $ ruby tr.rb > tree.txt
>
> robert@fussel /cygdrive/c/Temp
> $ wc -l tree.txt
> 897 tree.txt
>
> robert@fussel /cygdrive/c/Temp
> $ cat tr.rb
> require 'pp'
> ins = lambda {|h,k| h[k] = Hash.new(&ins)}
> tree = Hash.new(&ins)
> ObjectSpace.each_object(Class) {|cl| tree[cl.superclass][cl] = tree[cl]}
> pp tree

Nice! Small refinement for tree of Exceptions:

  tree[cl.superclass][cl] = tree[cl] if cl <= Exception

Regards,
Sean