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#--
# Copyright:: Copyright (c) Chef Software Inc.
# License:: Apache License, Version 2.0
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

require_relative "../decorator"

class Chef
  class Decorator
    # Lazy wrapper to delay construction of an object until a method is
    # called against the object.
    #
    # @example
    #
    #     def foo
    #       puts "allocated"
    #       "value"
    #     end
    #
    #     a = Chef::Decorator::Lazy.new { foo }
    #
    #     puts "started"
    #     a
    #     puts "still lazy"
    #     puts a
    #
    #   outputs:
    #
    #     started
    #     still lazy
    #     allocated
    #     value
    #
    # @since 12.10.x
    class Lazy < Decorator
      def initialize(&block)
        super
        @block = block
      end

      def __getobj__
        __setobj__(@block.call) unless defined?(@delegate_sd_obj)
        super
      end

    end
  end
end