Module | Sequel::Plugins::Composition::ClassMethods |
In: |
lib/sequel/plugins/composition.rb
|
composition_module | [R] | A module included in the class holding the composition getter and setter methods. |
compositions | [R] | A hash with composition name keys and composition reflection hash values. |
Define a composition for this model, with name being the name of the composition. You must provide either a :mapping option or both the :composer and :decomposer options.
Options:
# Uses columns year, month, and day in the current model # Uses year, month, and day methods in the composition object :mapping=>[:year, :month, :day] # Uses columns year, month, and day in the current model # Uses y, m, and d methods in the composition object where # for example y in the composition object represents year # in the model object. :mapping=>[[:year, :y], [:month, :m], [:day, :d]]
# File lib/sequel/plugins/composition.rb, line 60 60: def composition(name, opts={}) 61: opts = opts.dup 62: compositions[name] = opts 63: if mapping = opts[:mapping] 64: keys = mapping.map{|k| k.is_a?(Array) ? k.first : k} 65: if !opts[:composer] 66: late_binding_class_option(opts, name) 67: klass = opts[:class] 68: class_proc = proc{klass || constantize(opts[:class_name])} 69: opts[:composer] = proc do 70: if values = keys.map{|k| send(k)} and values.any?{|v| !v.nil?} 71: class_proc.call.new(*values) 72: else 73: nil 74: end 75: end 76: end 77: if !opts[:decomposer] 78: setter_meths = keys.map{|k| "#{k}=""#{k}="} 79: cov_methods = mapping.map{|k| k.is_a?(Array) ? k.last : k} 80: setters = setter_meths.zip(cov_methods) 81: opts[:decomposer] = proc do 82: if (o = compositions[name]).nil? 83: setter_meths.each{|sm| send(sm, nil)} 84: else 85: setters.each{|sm, cm| send(sm, o.send(cm))} 86: end 87: end 88: end 89: end 90: raise(Error, "Must provide :composer and :decomposer options, or :mapping option") unless opts[:composer] && opts[:decomposer] 91: define_composition_accessor(name, opts) 92: end
Define getter and setter methods for the composition object.
# File lib/sequel/plugins/composition.rb, line 102 102: def define_composition_accessor(name, opts={}) 103: include(@composition_module ||= Module.new) unless composition_module 104: composer = opts[:composer] 105: composition_module.class_eval do 106: define_method(name) do 107: compositions.include?(name) ? compositions[name] : (compositions[name] = instance_eval(&composer)) 108: end 109: define_method("#{name}=") do |v| 110: modified! 111: compositions[name] = v 112: end 113: end 114: end