my %jobNames;
    my $errors;

        # Ensure that there is only one job with the given
        # name. FIXME: this check will become unnecessary after we
        # remove support for multiple values per jobset input.
        if (defined $jobNames{$job->{jobName}}) {
            $errors .= "error: there are multiple jobs named ‘$job->{jobName}’\n\n";
            next;
        }
        $jobNames{$job->{jobName}} = 1;

    my %jobNames;
    my $errors;
    foreach my $job (@{$jobs->{job}}) {
        $jobNames{$job->{jobName}}++;
        if ($jobNames{$job->{jobName}} == 2) {
            $errors .= "warning: there are multiple jobs named ‘$job->{jobName}’; support for this will go away soon!\n\n";
        }
    }