[root@jbossproxy01 ~]# puppet -v /tmp/test.pp 
info: Loading fact domain
info: Loading fact apache_version
info: Loading fact netmask
info: Loading fact hardware_platform
Could not parse for environment development: Could not match '${ipaddress}_${interface_alias}' at /tmp/test.pp:2


[root@jbossproxy01 ~]# cat !$
cat /tmp/test.pp
$interface_alias = "eth0:0"
$foo = ${ipaddress}_${interface_alias}
notice $foo