Class: Hashie::Nash

Inherits:
Dash
  • Object
show all
Includes:
PrettyInspect
Defined in:
lib/nashie.rb

Overview

A Nash is a Nested Defined Hash and is an extension of a Dash A Nash allows you to create complex assignments composing of several nested Dashes

Nashes are useful when you need to create a lightweigth nested data object, ideal for validating JSON

Class Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(attributes = {}, &block) ⇒ Nash

You may initialize a Dash with an attributes hash just like you would many other kinds of data objects.



99
100
101
102
103
104
105
106
107
 
# File 'lib/nashie.rb', line 99

def initialize(attributes = {}, &block)
  super(attributes, &block) 
  
  # override whatever Dash has set
  attributes.each_pair do |att, value|
    self.send((att.to_s + '=').to_sym,value) 
  end if attributes
  assert_required_properties_set!
end

Class Attribute Details

.class_properties ⇒ Object (readonly)

Returns the value of attribute class_properties.



18
19
20
 
# File 'lib/nashie.rb', line 18

def class_properties
  @class_properties
end

Class Method Details

.inherited(klass) ⇒ Object 



87
88
89
90
91
92
93
94
 
# File 'lib/nashie.rb', line 87

def self.inherited(klass)
  super
  (@subclasses ||= Set.new) << klass
  klass.instance_variable_set('@properties', self.properties.dup)
  klass.instance_variable_set('@defaults', self.defaults.dup)
  klass.instance_variable_set('@required_properties', self.required_properties.dup)
  klass.instance_variable_set('@class_properties', self.class_properties.dup)
end

.property(property_name, options = {}) ⇒ Object

Defines a property on the Nash. Options are as follows:

  • :default - Specify a default value for this property, to be returned before a value is set on the property in a new Nash.

  • :required - Specify the value as required for this property, to raise an error if a value is unset in a new or existing Nash.

  • :class - Specify a class for this property that should be instantiated when an assignment is made to this property.



37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
 
# File 'lib/nashie.rb', line 37

def self.property(property_name, options = {})
      property_name = property_name.to_sym

      self.properties << property_name

      if options.has_key?(:class)
        class_name = options[:class].to_s
        class_properties[property_name] = class_name if options.delete(:class)
        class_eval <<-ACCESSORS
          def #{property_name}(&block)
            self.[](#{property_name.to_s.inspect}, &block)
          end

          def #{property_name}=(value)
            self.[]=(#{property_name.to_s.inspect}, #{class_properties[property_name]}.new(value))
          end
          
        ACCESSORS
        
        
      elsif
        class_properties[property_name] = nil
      end

      if options.has_key?(:default)
        self.defaults[property_name] = options[:default]
      elsif self.defaults.has_key?(property_name)
        self.defaults.delete property_name
      end

      unless instance_methods.map { |m| m.to_s }.include?("#{property_name}=")
        class_eval <<-ACCESSORS
          def #{property_name}(&block)
            self.[](#{property_name.to_s.inspect}, &block)
          end

          def #{property_name}=(value)
            self.[]=(#{property_name.to_s.inspect}, value)
          end
        ACCESSORS
      end

      if defined? @subclasses
        @subclasses.each { |klass| klass.property(property_name, options) }
      end
      required_properties << property_name if options.delete(:required)
end