a bug?

result with line 4 removed.sh

$  puppet apply test.pp                                                                                                      
warning: Scope(Class[Foo]): Could not look up qualified variable 'bar::var'; class bar has not been evaluated at /tmp/test.pp:4
notice: undef
notice: /Stage[main]/Foo/Notify[undef]/message: defined 'message' as 'undef'
notice: Finished catalog run in 0.03 seconds

# The same is produced if I append to the manifest the line 'Class['foo'] -> Class['bar']'

result.sh

$ puppet apply test.pp                                                                                                      
Duplicate definition: Class[Bar] is already defined; cannot redefine at /tmp/test.pp:11

test.pp

include foo

class foo {
 require bar
 notify { $bar::var : }
}

class bar ($var='bz') {
}

class { 'bar': }