begin_instruct(Send email)_param({str} from, to, cc, subject, msg, {html}, htmlmsg)_opt({cred}, login)_ns(rosettacode);
    set_thread(linger);
    find_thing()_first()_email()
        ? with_found()_label(emailer);
        : exit_instruct[]_err(Sorry, no one can send emails!);
    ;
    with_[emailer]_format(html)
        ? with_[emailer]_cred[login]_email[htmlmsg]_from[from]_to[to]_cc[cc]_subject[subject];
            : exit_instruct[]_err(Something went wrong with the email);
        : with_[emailer]_cred[login]_email[msg]_from[from]_to[to]_cc[cc]_subject[subject];
            : exit_instruct[]_err(Something went wrong with the email);
    ;
    reset_thread();
end_instruct[];

set_namespace(rosettacode);

// Set up credentials
add_var({cred}, mycred)_server(esvr1)_username(bob)_password(p@$$w0rd);  // Other credentials can be added here

// Send email:
exec_instruct(Send email)_param()
    _from(bob@bobmail.com.invalid)  // It is at the discretion of the caller to use this from address
    _to(fred@bobmail.com.invalid)
    _cc(jill@bobmail.com.invalid)
    _subject(Rosettacode wants me to send an email!)
    _msg(This is the body of my email.)
    _htmlmsg(<b>This is the body of my email, in bold</b>)
    _login[mycred]
_me();

reset_namespace();