Class YARD::Options
In: lib/yard/options.rb
Parent: Object

Generalized options class for passing around large amounts of options between objects.

The options class exists for better visibility and documentability of options being passed through to other objects. Because YARD has parser and template architectures that are heavily reliant on options, it is necessary to make these option keys easily visible and understood by developers. Since the options class is more than just a basic Hash, the subclass can provide aliasing and convenience methods to simplify option property access, and, if needed, support backward-compatibility for deprecated key names.

Hash and OpenStruct-like Access

Although the options class allows for Hash-like access (opts[:key]), the recommended mechanism for accessing an option key will be via standard method calls on attributes

The options class can also act as an open ended key value storage structure (like a Hash or OpenStruct), and allows for setting and getting of unregistered option keys. This methodology is not recommended, however, and is only supported for backward compatibility inside YARD. Whenever possible, developers should define all keys used by an options class.

Declaring Default Values

Note that the options class can contain default value definitions for certain options, but to initialize these defaults, {reset_defaults} must be called manually after initialization; the options object is always created empty until defaults are applied.

@abstract Subclasses should define (and document) custom attributes that are expected

  to be made available as option keys.

@example Defining an Options class with custom option keys

  class TemplateOptions < YARD::Options
    # @return [Symbol] the output format to generate templates in
    attr_accessor :format

    # @return [Symbol] the template to use when generating output
    attr_accessor :template
  end

@example Initializing default option values

  class TemplateOptions < YARD::Options
    def reset_defaults
      super
      self.format = :html
      self.template = :default
      self.highlight = true
      # ...
    end
  end

@example Using default_attr to create default attributes

  class TemplateOptions < YARD::Options
    default_attr :format, :html
    default_attr :template, :default
    default_attr :highlight, true
  end

@example Deprecating an option while still supporting it

  class TemplateOptions < YARD::Options
    # @return [Boolean] if syntax highlighting should be performed on code blocks.
    #   Defaults to true.
    attr_accessor :highlight

    # @deprecated Use {#highlight} instead.
    # @return [Boolean] if no syntax highlighting should be performs on code blocks.
    #   Defaults to false.
    attr_accessor :no_highlight
    def no_highlight=(value) @highlight = !value end
    def no_highlight; !highlight end
  end

Methods

==   []   []=   default_attr   delete   each   inspect   merge   method_missing   reset_defaults   tap   to_hash   update  

Public Class methods

@!macro [attach] yard.default_attr

  @!attribute $1

Defines an attribute named key and sets a default value for it

@example Defining a default option key

  default_attr :name, 'Default Name'
  default_attr :time, lambda { Time.now }

@param [Symbol] key the option key name @param [Object, Proc] default the default object value. If the default

  value is a proc, it is executed upon initialization.

Public Instance methods

@return [Boolean] whether another Options object equals the

  keys and values of this options object

Delegates calls with Hash syntax to actual method with key name

@example Calling on an option key with Hash syntax

  options[:format] # equivalent to: options.format

@param [Symbol, String] key the option name to access @return the value of the option named key

Delegates setter calls with Hash syntax to the attribute setter with the key name

@example Setting an option with Hash syntax

  options[:format] = :html # equivalent to: options.format = :html

@param [Symbol, String] key the optin to set @param [Object] value the value to set for the option @return [Object] the value being set

Deletes an option value for key

@param [Symbol, String] key the key to delete a value for @return [Object] the value that was deleted

Yields over every option key and value @yield [key, value] every option key and value @yieldparam [Symbol] key the option key @yieldparam [Object] value the option value @return [void]

Inspects the object

Creates a new options object and sets options hash or object value onto that object.

@param [Options, Hash] opts @return [Options] the newly created options object @see update

Handles setting and accessing of unregistered keys similar to an OpenStruct object.

@note It is not recommended to set and access unregistered keys on

  an Options object. Instead, register the attribute before using it.

Resets all values to their defaults.

@abstract Subclasses should override this method to perform custom

  value initialization if not using {default_attr}. Be sure to call
  +super+ so that default initialization can take place.

@return [void]

@return [Hash] Converts options object to an options hash. All keys

  will be symbolized.

Updates values from an options hash or options object on this object. All keys passed should be key names defined by attributes on the class.

@example Updating a set of options on an Options object

  opts.update(:template => :guide, :type => :fulldoc)

@param [Hash, Options] opts @return [self]

[Validate]