better name for the module

lib/spec/example/example_methods.rb

@@ -53,13 +53,18 @@ def execute(run_options, instance_variables) # :nodoc:
         success = execution_error.nil? || ExamplePendingError === execution_error
       end
 
-      module Aliases
+      module BlockAliases
         alias_method :to,     :should
         alias_method :to_not, :should_not
       end
 
+      # Extends the submitted block with aliases to and to_not
+      # for should and should_not. Allows expectations like this:
+      #
+      #   expect { this_block }.to change{this.expression}.from(old_value).to(new_value)
+      #   expect { this_block }.to raise_error
       def expect(&block)
-        block.extend Aliases
+        block.extend BlockAliases
       end
 
       def eval_each_fail_fast(blocks) # :nodoc: