lib/dependor/instantiator.rb in dependor-0.0.6 vs lib/dependor/instantiator.rb in dependor-1.0.0

@@ -1,14 +1,24 @@
 module Dependor
   class Instantiator
     def initialize(injector)
       @injector = injector
+      @constructor_params = {}
     end
 
     def instantiate(klass)
-      params = klass.instance_method(:initialize).parameters
-      dependency_names = params.select{|type, name| type == :req}.map{|type, name| name}
-      dependencies = dependency_names.map{|name| @injector.get(name)}
+      dependencies = dependecy_names_for(klass).map{|name| @injector.get(name)}
       return klass.new(*dependencies)
+    end
+
+    private
+
+    def dependecy_names_for(klass)
+      @constructor_params[klass] ||= get_constructor_params(klass)
+    end
+
+    def get_constructor_params(klass)
+      params = klass.instance_method(:initialize).parameters
+      params.select{|type, name| type == :req}.map{|type, name| name}
     end
   end
 end