Method: Parameters#parameter

Defined in:
lib/parameters/parameters.rb

#parameter(name, options = {}) ⇒ InstanceParam

Adds a new parameter to the object.

Examples:

obj.parameter('var')

obj.parameter('var',:default => 3, :description => 'my variable')

Parameters:

  • name (Symbol, String) —

    The name for the new instance parameter.

  • options (Hash) (defaults to: {}) —

    Additional options.

Options Hash (options):

  • :type (Class, Array[Class]) —

    The type to enforce the new parameter values to.

  • :default (Object, Proc) —

    The default value for the new parameter.

  • :description (String) —

    The description for the new parameter.

Returns:



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# File 'lib/parameters/parameters.rb', line 78

def parameter(name,options={})
  name    = name.to_sym

  instance_eval %{
    # define the reader method for the parameter
    def #{name}
      get_param(#{name.inspect}).value
    end

    # define the writer method for the parameter
    def #{name}=(new_value)
      get_param(#{name.inspect}).value = new_value
    end

    def #{name}?
      !!get_param(#{name.inspect}).value
    end
  }

  # create the new parameter
  new_param = InstanceParam.new(
    self,
    name,
    options[:type],
    options[:description],
    options[:default]
  )

  # add the new parameter
  self.params[name] = new_param
  return new_param
end