From: J J <jj5412@...>
Date: 2001-05-04T11:11:24+09:00
Subject: [ruby-talk:14612] Re: Design by contract - problem with DbC

One small problem, DbC doesn't check the invariant after the constructor,
although dbc.rb line 274 says it should.

require 'DbC'

class Test
  def initialize
    @n = 25
  end

  def invariant
    @n == 10
  end
end

begin
  t = Test.new
rescue
  puts "Exception thrown, good"
else
  puts "No exception thrown, bad"
end

test.rb doesn't appear to test for this. I would fix it, but I'm still to
green in Ruby.

Regards,
  JJ

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> > > Any interest/thoughts on implementing simple design
> > > by contract in Ruby?
> > You might want to check out Andy Hunt's
> > implementation:
> > http://www.pragmaticprogrammer.com/ruby/downloads/dbc.html
> >
> > Chad