Added new section on Hash#select. Bettered the text in the introduction to hashes example.

docs/Hashes in Ruby /01 - Introduction to Ruby Hashes.haml

@@ -7,7 +7,7 @@ title - Introduction to Ruby Hashes
     'associative arrays', 'dictionary', 'HashMap' etc. in other languages    
   %p
     A blank hash can be declared using two curly braces <code>{}</code>. Here is 
-    an example of a Hash in Ruby:
+    an example of a Hash, with some items in it:
 
   %p
     %pre
@@ -65,13 +65,13 @@ restaurant_menu = {
 
 .section :fetch_from_a_hash, "Fetch values from a Hash", 167
   %p
-    You can retrieve values from a Hash object using <code>[]</code> operator.
+    You can retrieve values from a Hash object using the <code>[]</code> operator.
     The key of the required value should be enclosed within these square brackets.
 
   %p
     Now try finding the price of a Burger from the <code>restaurant_menu</code> hash:
-    write the name of the object, follow it with a square bracket, and place the 
-    key inside the brackets. In this case the key is a string so enclose the key
+    write the name of the hash, and place the key inside the <code>[]</code>.
+    In this case the key is a string so enclose the key
     in quotes.
 
   !enchant 3339

docs/Hashes in Ruby /02 - Iterating over Hashes.haml

@@ -102,3 +102,38 @@ restaurant_menu.keys
       pp user_code
     DATA
   !release
+
+.section :selecting_values_from_a_hash, "Selecting values from a Hash"
+  %p
+    You can select key-value pairs from the hash, which satisfy a condition - using the <code>select</code> method.
+    It will return a new hash with just the items which satisfied the condition.
+
+  %p
+    Try getting items which cost less than 10 from the <code>restaurant_menu</code> hash:
+
+  !enchant
+    exercise!
+    short_name :selecting_values_from_a_hash_examples
+    starting_code <<-DATA
+restaurant_menu = { "Burger" => 5, "Pizza" => 12, "Coffee" => 1 }
+# your code here
+    DATA
+
+    specs <<-DATA
+      it "picks items which cost less than 10" do
+        user_code.should == {"Burger" => 5, "Coffee" => 1}
+      end
+    DATA
+
+    solution <<-DATA
+restaurant_menu = { "Burger" => 5, "Pizza" => 12, "Coffee" => 1 }
+restaurant_menu.select { |item, price| price < 10 }
+    DATA
+
+    code_wrapper <<-DATA
+      def user_code
+        <%= user_code %>
+      end
+        pp user_code
+    DATA
+  !release