lib/hashformer.rb in hashformer-0.2.1 vs lib/hashformer.rb in hashformer-0.2.2

@@ -7,24 +7,25 @@
 
 require 'hashformer/version'
 require 'hashformer/generate'
 
 
-# This module contains the Hashformer methods for transforming Ruby Hash objects
-# from one form to another.
+# This module contains the Hashformer methods for transforming Ruby Hash
+# objects from one form to another.
 #
 # See README.md for examples.
 module Hashformer
   # Transforms +data+ according to the specification in +xform+.  The
   # transformation specification in +xform+ is a Hash specifying an input key
-  # name (e.g. a String or Symbol) or transforming lambda for each output key
-  # name.  If +validate+ is true, then ClassyHash::validate will be used to
-  # validate the input and output data formats against the :@__in_schema and
-  # :@__out_schema keys within +xform+, if specified.
+  # name (e.g. a String or Symbol), generator, or transforming lambda for each
+  # output key name.  If +validate+ is true, then ClassyHash::validate will be
+  # used to validate the input and output data formats against the
+  # :@__in_schema and :@__out_schema keys within +xform+, if specified.
   #
-  # Nested transformations can be specified by calling Hashformer::transform
-  # again inside of a lambda.
+  # Nested transformations can be specified by using a Hash as the
+  # transformation value, or by calling Hashformer.transform again inside of a
+  # lambda.
   #
   # If a value in +xform+ is a Proc, the Proc will be called with the input
   # Hash, and the return value of the Proc used as the output value.
   #
   # If a key in +xform+ is a Proc, the Proc will be called with the exact
@@ -44,30 +45,33 @@
     out = {}
     xform.each do |key, value|
       next if key == :__in_schema || key == :__out_schema
 
       key = key.call(value, data) if key.respond_to?(:call)
-      out[key] = self.get_value(data, value)
+      out[key] = self.get_value(data, value, xform)
     end
 
     validate(out, xform[:__out_schema], 'output') if validate
 
     out
   end
 
   # Returns a value for the given +key+, method chain, or callable on the given
-  # +input_hash+.
-  def self.get_value(input_hash, key)
+  # +input_hash+.  If +xform+ is not nil, then Hashe keys will be processed
+  # with Hashformer.transform.
+  def self.get_value(input_hash, key, xform = nil)
     if Hashformer::Generate::Chain::Receiver === key
       # Had to special case chains to allow chaining .call
       key.__chain.call(input_hash)
+    elsif Hashformer::Generate::Constant === key
+      key.value
     elsif key.respond_to?(:call)
       key.call(input_hash)
+    elsif key.is_a?(Hash)
+      transform(input_hash, key)
     else
       input_hash[key]
     end
-
-    # TODO: add support for nested output hashes
   end
 
   private
   # Validates the given data against the given schema, at the given step.
   def self.validate(data, schema, step)