1 files changed, 88 insertions, 1 deletions

diff --git a/lib/irb/notifier.rb b/lib/irb/notifier.rb
index d20679da4a..effb12c30d 100644
--- a/lib/irb/notifier.rb
+++ b/lib/irb/notifier.rb
@@ -13,6 +13,7 @@ require "e2mmap"
 require "irb/output-method"
 
 module IRB
+  # An output formatter used internally by the lexer.
   module Notifier
     extend Exception2MessageMapper
     def_exception :ErrUndefinedNotifier,
@@ -20,59 +21,100 @@ module IRB
     def_exception :ErrUnrecognizedLevel,
       "unrecognized notifier level: %s is specified"
 
+    # Define a new Notifier output source, returning a new CompositeNotifier
+    # with the given +prefix+ and +output_method+.
+    #
+    # The optional +prefix+ will be appended to all objects being inspected
+    # during output, using the given +output_method+ as the output source. If
+    # no +output_method+ is given, StdioOuputMethod will be used, and all
+    # expressions will be sent directly to STDOUT without any additional
+    # formatting.
     def def_notifier(prefix = "", output_method = StdioOutputMethod.new)
       CompositeNotifier.new(prefix, output_method)
     end
     module_function :def_notifier
 
+    # An abstract class, or superclass, for CompositeNotifier and
+    # LeveledNotifier to inherit. It provides several wrapper methods for the
+    # OutputMethod object used by the Notifier.
     class AbstractNotifier
+      # Creates a new Notifier object
       def initialize(prefix, base_notifier)
 	@prefix = prefix
 	@base_notifier = base_notifier
       end
 
+      # The +prefix+ for this Notifier, which is appended to all objects being
+      # inspected during output.
       attr_reader :prefix
 
+      # A wrapper method used to determine whether notifications are enabled.
+      #
+      # Defaults to +true+.
       def notify?
 	true
       end
 
+      # See OutputMethod#print for more detail.
       def print(*opts)
 	@base_notifier.print prefix, *opts if notify?
       end
 
+      # See OutputMethod#printn for more detail.
       def printn(*opts)
 	@base_notifier.printn prefix, *opts if notify?
       end
 
+      # See OutputMethod#printf for more detail.
       def printf(format, *opts)
 	@base_notifier.printf(prefix + format, *opts) if notify?
       end
 
+      # See OutputMethod#puts for more detail.
       def puts(*objs)
 	if notify?
 	  @base_notifier.puts(*objs.collect{|obj| prefix + obj.to_s})
 	end
       end
 
+      # Same as #ppx, except it uses the #prefix given during object
+      # initialization.
+      # See OutputMethod#ppx for more detail.
       def pp(*objs)
 	if notify?
 	  @base_notifier.ppx @prefix, *objs
 	end
       end
 
+      # Same as #pp, except it concatenates the given +prefix+ with the #prefix
+      # given during object initialization.
+      #
+      # See OutputMethod#ppx for more detail.
       def ppx(prefix, *objs)
 	if notify?
 	  @base_notifier.ppx @prefix+prefix, *objs
 	end
       end
 
+      # Execute the given block if notifications are enabled.
       def exec_if
 	yield(@base_notifier) if notify?
       end
     end
 
+    # A class that can be used to create a group of notifier objects with the
+    # intent of representing a leveled notification system for irb.
+    #
+    # This class will allow you to generate other notifiers, and assign them
+    # the appropriate level for output.
+    #
+    # The Notifier class provides a class-method Notifier.def_notifier to
+    # create a new composite notifier. Using the first composite notifier
+    # object you create, sibling notifiers can be initialized with
+    # #def_notifier.
     class CompositeNotifier<AbstractNotifier
+      # Create a new composite notifier object with the given +prefix+, and
+      # +base_notifier+ to use for output.
       def initialize(prefix, base_notifier)
 	super
 
@@ -80,17 +122,39 @@ module IRB
 	@level_notifier = D_NOMSG
       end
 
+      # List of notifiers in the group
       attr_reader :notifiers
 
+      # Creates a new LeveledNotifier in the composite #notifiers group.
+      #
+      # The given +prefix+ will be assigned to the notifier, and +level+ will
+      # be used as the index of the #notifiers Array.
+      #
+      # This method returns the newly created instance.
       def def_notifier(level, prefix = "")
 	notifier = LeveledNotifier.new(self, level, prefix)
 	@notifiers[level] = notifier
 	notifier
       end
 
+      # Returns the leveled notifier for this object
       attr_reader :level_notifier
       alias level level_notifier
 
+      # Sets the leveled notifier for this object.
+      #
+      # When the given +value+ is an instance of AbstractNotifier,
+      # #level_notifier is set to the given object.
+      #
+      # When an Integer is given, #level_notifier is set to the notifier at the
+      # index +value+ in the #notifiers Array.
+      #
+      # If no notifier exists at the index +value+ in the #notifiers Array, an
+      # ErrUndefinedNotifier exception is raised.
+      #
+      # An ErrUnrecognizedLevel exception is raised if the given +value+ is not
+      # found in the existing #notifiers Array, or an instance of
+      # AbstractNotifier
       def level_notifier=(value)
 	case value
 	when AbstractNotifier
@@ -107,38 +171,61 @@ module IRB
       alias level= level_notifier=
     end
 
+    # A leveled notifier is comparable to the composite group from
+    # CompositeNotifier#notifiers.
     class LeveledNotifier<AbstractNotifier
       include Comparable
 
+      # Create a new leveled notifier with the given +base+, and +prefix+ to
+      # send to AbstractNotifier.new
+      #
+      # The given +level+ is used to compare other leveled notifiers in the
+      # CompositeNotifier group to determine whether or not to output
+      # notifications.
       def initialize(base, level, prefix)
 	super(prefix, base)
 
 	@level = level
       end
 
+      # The current level of this notifier object
       attr_reader :level
 
+      # Compares the level of this notifier object with the given +other+
+      # notifier.
+      #
+      # See the Comparable module for more information.
       def <=>(other)
 	@level <=> other.level
       end
 
+      # Whether to output messages to the output method, depending on the level
+      # of this notifier object.
       def notify?
 	@base_notifier.level >= self
       end
     end
 
+    # NoMsgNotifier is a LeveledNotifier that's used as the default notifier
+    # when creating a new CompositeNotifier.
+    #
+    # This notifier is used as the +zero+ index, or level +0+, for
+    # CompositeNotifier#notifiers, and will not output messages of any sort.
     class NoMsgNotifier<LeveledNotifier
+      # Creates a new notifier that should not be used to output messages.
       def initialize
 	@base_notifier = nil
 	@level = 0
 	@prefix = ""
       end
 
+      # Ensures notifications are ignored, see AbstractNotifier#notify? for
+      # more information.
       def notify?
 	false
       end
     end
 
-    D_NOMSG = NoMsgNotifier.new
+    D_NOMSG = NoMsgNotifier.new # :nodoc:
   end
 end