--- /dev/null
+#
+# is_mac_address.rb
+#
+
+module Puppet::Parser::Functions
+ newfunction(:is_mac_address, :type => :rvalue, :doc => <<-EOS
+Returns true if the string passed to this function is a valid mac address.
+ EOS
+ ) do |arguments|
+
+ if (arguments.size != 1) then
+ raise(Puppet::ParseError, "is_mac_address(): Wrong number of arguments "+
+ "given #{arguments.size} for 1")
+ end
+
+ mac = arguments[0]
+
+ if /^[a-fA-F0-9]{1,2}:[a-fA-F0-9]{1,2}:[a-fA-F0-9]{1,2}:[a-fA-F0-9]{1,2}:[a-fA-F0-9]{1,2}:[a-fA-F0-9]{1,2}$/.match(mac) then
+ return true
+ else
+ return false
+ end
+
+ end
+end
+
+# vim: set ts=2 sw=2 et :