4 files changed, 73 insertions, 11 deletions
diff --git a/lib/psych.rb b/lib/psych.rb
index 9c6397d..aaec4a7 100644
--- a/lib/psych.rb
+++ b/lib/psych.rb
@@ -2,6 +2,8 @@ require 'psych/nodes/node'
 require 'psych/nodes/stream'
 require 'psych/nodes/document'
 require 'psych/nodes/sequence'
+require 'psych/nodes/scalar'
+require 'psych/nodes/mapping'
 
 require 'psych/handler'
 require 'psych/tree_builder'
diff --git a/lib/psych/nodes/mapping.rb b/lib/psych/nodes/mapping.rb
new file mode 100644
index 0000000..b1137e1
--- /dev/null
+++ b/lib/psych/nodes/mapping.rb
@@ -0,0 +1,15 @@
+module Psych
+  module Nodes
+    ###
+    # This class represents a {YAML Mapping}[http://yaml.org/spec/1.1/#mapping].
+    class Mapping < Psych::Nodes::Node
+      def initialize anchor, tag, implicit, style
+        super()
+        @anchor   = anchor
+        @tag      = tag
+        @implicit = implicit
+        @style    = style
+      end
+    end
+  end
+end
diff --git a/lib/psych/nodes/scalar.rb b/lib/psych/nodes/scalar.rb
new file mode 100644
index 0000000..bfa494f
--- /dev/null
+++ b/lib/psych/nodes/scalar.rb
@@ -0,0 +1,35 @@
+module Psych
+  module Nodes
+    ###
+    # This class represents a {YAML Scalar}[http://yaml.org/spec/1.1/#id858081].
+    class Scalar < Psych::Nodes::Node
+      # The scalar value
+      attr_accessor :value
+
+      # The anchor value (if there is one)
+      attr_accessor :anchor
+
+      # The tag value (if there is one)
+      attr_accessor :tag
+
+      # Is this a plain scalar?
+      attr_accessor :plain
+
+      # Is this scalar quoted?
+      attr_accessor :quoted
+
+      # The style of this scalar
+      attr_accessor :style
+
+      def initialize value, anchor, tag, plain, quoted, style
+        super()
+        @value  = value
+        @anchor = anchor
+        @tag    = tag
+        @plain  = plain
+        @quoted = quoted
+        @style  = style
+      end
+    end
+  end
+end
diff --git a/lib/psych/tree_builder.rb b/lib/psych/tree_builder.rb
index c7e46fb..6a10354 100644
--- a/lib/psych/tree_builder.rb
+++ b/lib/psych/tree_builder.rb
@@ -16,23 +16,33 @@ module Psych
       @stack.first
     end
 
-    def start_stream encoding
-      super
-      @stack.push Nodes::Stream.new encoding
+    %w{
+      Document
+      Sequence
+      Mapping
+    }.each do |node|
+      class_eval %{
+        def start_#{node.downcase}(*args)
+          super
+          n = Nodes::#{node}.new(*args)
+          @stack.last.children << n
+          @stack.push n
+        end
+
+        def end_#{node.downcase}(*args)
+          @stack.pop
+        end
+      }
     end
 
-    def start_document version = [], tag_directives = [], implicit = true
+    def start_stream encoding
       super
-      doc = Nodes::Document.new version, tag_directives, implicit
-      @stack.last.children << doc
-      @stack.push doc
+      @stack.push Nodes::Stream.new encoding
     end
 
-    def start_sequence anchor = nil, tag = nil, implicit = true, style = BLOCK_SEQUENCE_STYLE
+    def scalar(*args)
       super
-      seq = Nodes::Sequence.new anchor, tag, implicit, style
-      @stack.last.children << seq
-      @stack.push seq
+      @stack.last.children << Nodes::Scalar.new(*args)
     end
   end
 end