meta::function('load-state', <<'EOF');
my ($state_name) = @_;
my $state = retrieve("state::$state_name");
&{'save-state'}('_');     # Make a backup
delete $data{$_} for grep ! /^state::/, keys %data;
%externalized_functions = ();
eval($state);             # Apply the new state
warn $@ if $@;
verify();                 # Make sure it worked
EOF