BEGIN {
    my @yaml_classes = qw{YAML::XS YAML::Syck YAML::Tiny YAML};
    my $yaml_class = first { eval "use $_; 1" } @yaml_classes
        or die "Unable to load any of these YAML classes: @yaml_classes";

    # Only expecting whatever YAML class is loaded to export these functions
    my @yaml_funcs = qw{Dump Load};
    no strict 'refs';
    my %yaml_exports = map { $_ => 1 } @{$yaml_class . "::EXPORT"};
    $yaml_exports{$_} or die "$yaml_class doesn't export '$_'" for @yaml_funcs;
}