Module: HammerBuilder::DynamicClasses

Included in:
Abstract
Defined in:
lib/hammer_builder/dynamic_classes.rb

Overview

When extended into a class it enables easy defining and extending classes in the class.

class A
  extend DynamicClasses
  dynamic_classes do
    def_class :A do
      def to_s
        'a'
      end
    end
    def_class :B, :A do
      class_eval <<-RUBYCODE, __FILE__, __LINE__+1
        def to_s
          super + 'b'
        end
      RUBYCODE
    end
  end
end

class B < A
end

class C < A
  dynamic_classes do
    extend_class :A do
      def to_s
        'aa'
      end
    end
  end
end

puts A.dc[:A] # => #<Class:0x00000001d449b8(A.dc[:A])>
puts B.dc[:A] # => #<Class:0x00000001d42398(B.dc[:A])>
puts B.dc[:A].new # => a
puts B.dc[:B].new # => ab
puts C.dc[:B].new # => aab

Last example is the most interesting. It prints ‘aab’ not ‘ab’ because of the extension in class C. Class :B has as ancestor extended class :A from C therefore the two ‘a’.

Defined Under Namespace

Modules: Describable Classes: ClassDefinition, ClassExtension, Classes, DescribableClass

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.extended(base) ⇒ Object

hook to create Classes instance



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# File 'lib/hammer_builder/dynamic_classes.rb', line 182

def self.extended(base)
  base.send :create_dynamic_classes
  super
end

Instance Method Details

#dynamic_classes {|Proc, nil| ... } ⇒ Classes Also known as: dc

call this to get access to Classes instance to define/extend classes inside definition calls Classes#load! to preload defined classes a Proc enables writing class definitions/extensions

Yields:

  • (Proc, nil) —

    definition

Returns:

  • (Classes) —

    when definition is nil



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# File 'lib/hammer_builder/dynamic_classes.rb', line 198

def dynamic_classes(&definition)
  if definition
    @dynamic_classes.instance_eval &definition
    # @dynamic_classes.load!
    nil
  else
    @dynamic_classes
  end
end

#inherited(base) ⇒ Object

hook to create Classes instance in descendants



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# File 'lib/hammer_builder/dynamic_classes.rb', line 188

def inherited(base)
  base.send :create_dynamic_classes
  super
end