ruby on rails - What's the difference between sending :include to class and directly defining method in second class definition? -

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recently had add method redmine's core class. unable use inheritance, i've done this:

require_dependency 'time_entry_query' class timeentryquery < query     def my_new_method(foo, bar)     end end

and works - method added new objects. however, i've seen declaring new method in own module instead , sending :include class, become mixin. here's example:

module patches   module someclasspatch     def my_new_method     end end

and somewhere in app's initialization:

someclass.send(:include, patches::someclasspatch) unless someclass.include? (patches::someclasspatch)

what's difference between these 2 methods , 1 should use?

there 2 differences:

  1. when use mixin, there clear place "patch" methods can live. if wonder "hmm, where's my_new_method" coming from, , at, say, timeentryquery.ancestors or timeentryquery.instance_method(:my_new_method).owner, return patches::someclasspatch. know have file named lib/patches/some_class_patch.rb somewhere find defined. (i try source_location well, not reliable.)

  2. mixing in module class makes module superclass of class being mixed into. so, if there my_new_method defined in timeentryquery, first option overwrite it, whereas in second option, method become super method of method. iow: second option, new method won't called unless existing method calls super.


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