Merge pull request #413 from mhaskel/fix

Check for string before copying

Author: cyberious

lib/puppet/parser/functions/is_domain_name.rb

@@ -13,16 +13,16 @@ module Puppet::Parser::Functions
         "given #{arguments.size} for 1")
     end
 
+    # Only allow string types
+    return false unless arguments[0].is_a?(String)
+
     domain = arguments[0].dup
 
     # Limits (rfc1035, 3.1)
     domain_max_length=255
     label_min_length=1
     label_max_length=63
 
-    # Only allow string types
-    return false unless domain.is_a?(String)
-
     # Allow ".", it is the top level domain
     return true if domain == '.'