1 files changed, 10 insertions, 1 deletions
diff --git a/ext/psych/lib/psych/coder.rb b/ext/psych/lib/psych/coder.rb
index 79e46dab1b..eff0cc3dcb 100644
--- a/ext/psych/lib/psych/coder.rb
+++ b/ext/psych/lib/psych/coder.rb
@@ -7,7 +7,7 @@ module Psych
   # called, respectively.
   class Coder
     attr_accessor :tag, :style, :implicit
-    attr_reader   :type, :map, :scalar, :seq
+    attr_reader   :type, :scalar, :seq
 
     def initialize tag
       @map        = {}
@@ -19,6 +19,14 @@ module Psych
       @scalar     = nil
     end
 
+    # Emit a map.  The coder will be yielded to the block.
+    def map tag = @tag, style = @style
+      @tag   = tag
+      @style = style
+      yield self if block_given?
+      @map
+    end
+
     # Emit a scalar with +value+ and +tag+
     def represent_scalar tag, value
       self.tag    = tag
@@ -53,6 +61,7 @@ module Psych
       @type = :map
       @map[k] = v
     end
+    alias :add :[]=
 
     def [] k
       @type = :map