Class: Module

Inherits:
Object
  • Object
show all
Defined in:
lib/core_ext.rb

Instance Method Summary collapse

Instance Method Details

#follows_the_rules! ⇒ Object

This declares that the current class has a rulebook with rules that it wants it’s instances to follow.

I picked this name because the probability of someone needing the method ‘follows_the_rules!’ (with a bang) is slim… hopefully.



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# File 'lib/core_ext.rb', line 7

def follows_the_rules!
  extend(MetaTools)
  include(MetaTools)
  
  meta_def(:def_class_rule) do |what_to_capture, &class_block|

    class_eval { @rulebook ||= Rulebook.new }.add(what_to_capture, &class_block)
    
    # unless respond_to?(:method_missing)
      meta_def(:method_missing) do |meth, *args, &block|

        matching_rules = @rulebook[meth]

        unless matching_rules.empty?
          rule = matching_rules.first
          rule_block = rule.block
          rule_captures = rule[meth].captures || []
          #rule_arity = rule_block.arity == -1 ? 0 : rule_block.arity
          # The above removes the possibility of optional arguments

          # Define the method
          unless meta_class.respond_to?(meth)
            meta_def(meth) do |*rule_args|
              rule_args = (rule_captures + rule_args)#.take(rule_arity)
              instance_exec(*rule_args, &rule_block)
            end
          end

          send(meth, *args, &block)
        else
          super(meth, *args, &block)
        end # matching_rules.empty?

      end # meta_def(:method_missing)

    # end # respond_to?(:method_missing)
    
  end # def_class_rule
  
  meta_def(:def_rule) do |what_to_capture, &class_block|

    (@rulebook ||= Rulebook.new).add(what_to_capture, &class_block)

    # unless respond_to?(:method_missing)
      define_method(:method_missing) do |meth, *args, &block|
        matching_rules = self.class.instance_variable_get(:@rulebook)[meth] 

        unless matching_rules.empty?
          rule = matching_rules.first
          rule_block = rule.block
          rule_captures = rule[meth].captures || []
          # rule_arity = rule_block.arity == -1 ? 0 : rule_block.arity
          # The above removes the possibility of optional arguments

          # Define the method
          unless meta_class.respond_to?(meth)
            meta_def(meth) do |*rule_args|
              rule_args = (rule_captures + rule_args)#.take(rule_arity)
              instance_exec(*rule_args, &rule_block)
            end
          end

          send(meth, *args, &block)
        else
          super(meth, *args, &block)
        end # matching_rules.empty?

      end # meta_def(:method_missing)

    # end # respond_to?(:method_missing)

  end # def_rule
  
end