TODO

• Also think about how to extend the DBC abilities. Invariants would be nice, but how to implement them?
• Add multi method dispatch facilities similar to those from dispatch.rb. It would be good if code could be shared between that and signatures.
• Write introductionary explanation of what we do and don’t and why we do so. Probably belongs into the README but should also appear in the RDoc output. split-s.blogspot.com/2005/02/quack-quack.html might be useful for explaining why this is better than doing the usual is-a typing of static languages.
• Perhaps teach the Rakefile how to export the SVN tree to the RubyForge project (see svn2cvs.tigris.org/)
• If we add DBC we probably ought to have ways of getting the pre and post checks as well as the in-variants as an Array of Procs or something like that.
• Make Method#signature return a meta object that allows you to do method.signature.matches?(*args) or something similar?

Done

• Add methods for querying signature meta information. (Unbound)Method#signature would return the original Module#signature arguments.
• Set up a RubyForge project and teach the Rakefile how to upload releases
• Contact the pragprog guys about DBC in Ruby: www.eng.cse.dmu.ac.uk/~hgs/projects/ruby_dbc.html
  • Done, might base post/pre-conditions implementation on that project
• Think about the kind of object adaption that matz discussed on his weblog: redhanded.hobix.com/inspect/staticTyping.html Also see www.python.org/peps/pep-0246.html and peak.telecommunity.com/DevCenter/MonkeyTyping

    adaption :from => Pathname, :to => String, :via => :to_str
    adaption :from => String, :to => Pathname do |string|
      Pathname.new(string)
    end
    adaption :from => String, :to => Pathname, :via => Pathname.method(:new)
  

  Perhaps make both :from and :to default to self so short forms are possible inside classes: (raise Exception when :to == :from)

    class String
      adaption :to => Pathname, :via => Pathname.method(:new)
      adaption :from => Pathname, :via => :to_str
  
      adaption :to => Symbol, :via => :to_sym
    end
  

  Might be nice to have conditional adaption routes:

    class Object
      adaption :to => String, :via => :to_str, :if => Contract::Check::Quack[:to_str]
      # perhaps also introduce this short form
      adaption :to => String, :via => :to_str, :if => :to_str
    end
  

  Perhaps :if should default to :via if :via is a Symbol which would allow the above to become

    class Object
      adaption :to => String, :via => :to_str
    end
  

  • Implemented.
• Think about implementing Contract#implies which would automatically trigger the inclusion of a Module on other Modules/Classes that do fulfills(contract).
  • Implemented.
• Module#fulfills(contract) — a way of stating that all instances of a Class should be checked against the contract after initialisation. This would always need to be called after defining a custom initialize().
• Read www.smalltalk.org/articles/
  • Has a few generic comments about static typing and dynamic typing.