Module: Traited

Defined in:
lib/traited.rb

Overview

Traited helps you doing configuration similar to class variables.

It’s built on a simple Hash, where keys are objects and the values the configuration. By using #ancestral_trait you will get nicely inherited configuration, where keys later in the ancestors will take precedence.

Examples:

usage


class Foo
  include Traited
  trait :hello => 'Hello'

  def initialize
    trait :hello => 'World!'
  end

  def show
    [class_trait[:hello], trait[:hello], ancestral_trait[:hello]]
  end
end

Foo.trait[:hello] # => "Hello"
foo = Foo.new
foo.trait[:hello] # => "World!"
foo.show          # => ["Hello", "World!", "World!"]

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.included(into) ⇒ Object 



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# File 'lib/traited.rb', line 30

def self.included(into)
  into.extend(self)
end

Instance Method Details

#ancestral_trait ⇒ Object

Builds a trait from all the ancestors, closer ancestors overwrite distant ancestors

class Foo

include Innate::Traited
trait :one => :eins, :first => :erstes

end

class Bar < Foo

trait :two => :zwei

end

class Foobar < Bar

trait :three => :drei, :first => :overwritten

end

Foobar.ancestral_trait # => => :drei, :two => :zwei, :one => :eins, :first => :overwritten



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# File 'lib/traited.rb', line 64

def ancestral_trait
  klass = self.kind_of?(Module) ? self : self.class
  ANCESTRAL_TRAITS[klass] ||=
  each_ancestral_trait({}){|hash, trait| hash.update(trait) }
end

#ancestral_trait_values(key) ⇒ Object 



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# File 'lib/traited.rb', line 70

def ancestral_trait_values(key)
  klass = self.kind_of?(Module) ? self : self.class
  cache = ANCESTRAL_VALUES[klass] ||= {}
  cache[key] ||= each_ancestral_trait([]){|array, trait|
    array << trait[key] if trait.key?(key) }
end

#class_trait ⇒ Object

trait for self.class if we are an instance



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# File 'lib/traited.rb', line 85

def class_trait
  respond_to?(:ancestors) ? trait : self.class.trait
end

#each_ancestral_trait(obj) ⇒ Object 



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# File 'lib/traited.rb', line 77

def each_ancestral_trait(obj)
  ancs = respond_to?(:ancestors) ? ancestors : self.class.ancestors
  ancs.unshift(self)
  ancs.reverse_each{|anc| yield(obj, TRAITS[anc]) if TRAITS.key?(anc) }
  obj
end

#trait(hash = nil) ⇒ Object 



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# File 'lib/traited.rb', line 34

def trait(hash = nil)
  if hash
    TRAITS[self] ||= {}
    result = TRAITS[self].merge!(hash)
    ANCESTRAL_VALUES.clear
    ANCESTRAL_TRAITS.clear
    result
  else
    TRAITS[self] || {}
  end
end