This recursively flattens multilevel hashes so you can get to them with a TT-ish syntax from HTML::Template. It should be straight-forward to modify if you also want arrayrefs to be recursively flattened too.
sub flatten {
my $hr = shift;
my %result;
while (my ($k, $v) = each %$hr) {
if (ref $v eq 'HASH') {
my $r = flatten($v);
$result{"$k.$_"} = $r->{$_} for keys %$r;
} else {
$result{$k} = $v;
}
}
\%result;
}
print Dumper flatten {
foo => {
in_foo => 1,
bar => 1,
baz => {
in_baz => 1
}
},
blah => 1
};
__END__
$VAR1 = {
'foo.bar' => 1,
'blah' => 1,
'foo.baz.in_baz' => 1,
'foo.in_foo' => 1
};