class Bundler::RubyVersion

def initialize(version, patchlevel, engine, engine_version)
  # The parameters to this method must satisfy the
  # following constraints, which are verified in
  # the DSL:
  #
  # * If an engine is specified, an engine version
  #   must also be specified
  # * If an engine version is specified, an engine
  #   must also be specified
  # * If the engine is "ruby", the engine version
  #   must not be specified, or the engine version
  #   specified must match the version.
  @version        = version
  @engine         = engine || "ruby"
  # keep track of the engine specified by the user
  @input_engine   = engine
  @engine_version = engine_version || version
  @patchlevel     = patchlevel
end