Hi,

I'm really new to dependency injection in general, but I hope I can help, 
though. I am aware of two libraries for what you want to do. Copland, first, 
is an Inversion of Control (IoC) container, based on the Hivemind IoC 
container for java.
As you said, there is no interface in Ruby, so Interface based injection is 
not supported. However, Type 2 IoC (Setter Injection) and type 3 IoC 
(Constructor Injection) are supported.
The second is Needle, which is a Dependency Injection container. I don't know 
much about it, except it supports a Service Locator mechanism.

By the way, the documentations are great for both ! Read them both and make 
your choice !

http://needle.rubyforge.org/
http://copland.rubyforge.org/

--
Olivier Renaud

Le lundi 29 janvier 2007 19:45, PerfectDayToChaseTornados a ?crit?:
> Hi All,
>
> I am a Java developer of many years & just starting to get into Ruby (&
> really enjoying it!). However I am used to 'coding by contract' using
> interfaces. This is especially great when using dependency injection
> (usually via Spring). It makes testing very easy, as 'mocks' can be written
> simply & then plugged in. I know that there isn't an equvalent for an
> interface in Ruby, but is there a pattern which would typically be used? I
> was wondering whether to create Modules in place of my interfaces & provide
> them with methods which throw Exceptions, thus forcing them to be
> overrriden in the classes that include them? Also how does one manage
> dependency injection in Ruby? Is there a good framework/library/pattern
> typically used for this, or are there good 'Ruby reasons' not to use DI?
>
> Many thanks