And ... ? What does the KOHA documentation say about what the parameter(s) of AddMember should be?

AddMember $borrowernumber = &AddMember(%borrower); insert new borrower into table Returns the borrowernumber upon success Returns as undef upon any db error without further processing

The function is

sub AddMember {
    my (%data) = @_;
    my $dbh = C4::Context->dbh;

    # generate a proper login if none provided
    $data{'userid'} = Generate_Userid( $data{'borrowernumber'}, $data{
+'firstname'}, $data{'surname'} )
      if ( $data{'userid'} eq '' || !Check_Userid( $data{'userid'} ) )
+;

    # add expiration date if it isn't already there
    unless ( $data{'dateexpiry'} ) {
        $data{'dateexpiry'} = GetExpiryDate( $data{'categorycode'}, C4
+::Dates->new()->output("iso") );
    }

    # add enrollment date if it isn't already there
    unless ( $data{'dateenrolled'} ) {
        $data{'dateenrolled'} = C4::Dates->new()->output("iso");
    }

    my $patron_category =
      Koha::Database->new()->schema()->resultset('Category')
      ->find( $data{'categorycode'} );
    $data{'privacy'} =
        $patron_category->default_privacy() eq 'default' ? 1
      : $patron_category->default_privacy() eq 'never'   ? 2
      : $patron_category->default_privacy() eq 'forever' ? 0
      :                                                    undef;
    # Make a copy of the plain text password for later use
    my $plain_text_password = $data{'password'};

    # create a disabled account if no password provided
    $data{'password'} = ($data{'password'})? hash_password($data{'pass
+word'}) : '!';
    $data{'borrowernumber'}=InsertInTable("borrowers",\%data);

    # If NorwegianPatronDBEnable is enabled, we set syncstatus to some
+thing that a
    # cronjob will use for syncing with NL
    if ( exists $data{'borrowernumber'} && C4::Context->preference('No
+rwegianPatronDBEnable') && C4::Context->preference('NorwegianPatronDB
+Enable') == 1 ) {
        Koha::Database->new->schema->resultset('BorrowerSync')->create
+({
            'borrowernumber' => $data{'borrowernumber'},
            'synctype'       => 'norwegianpatrondb',
            'sync'           => 1,
            'syncstatus'     => 'new',
            'hashed_pin'     => NLEncryptPIN( $plain_text_password ),
        });
    }

    # mysql_insertid is probably bad.  not necessarily accurate and my
+sql-specific at best.
    logaction("MEMBERS", "CREATE", $data{'borrowernumber'}, "") if C4:
+:Context->preference("BorrowersLog");

    AddEnrolmentFeeIfNeeded( $data{categorycode}, $data{borrowernumber
+} );

    return $data{'borrowernumber'};
}

=head2 Check_Userid

    my $uniqueness = Check_Userid($userid,$borrowernumber);

    $borrowernumber is optional (i.e. it can contain a blank value). I
+f $userid is passed with a blank $borrowernumber variable, the databa
+se will be checked for all instances of that userid (i.e. userid=? AN
+D borrowernumber != '').

    If $borrowernumber is provided, the database will be checked for e
+very instance of that userid coupled with a different borrower(number
+) than the one provided.

    return :
        0 for not unique (i.e. this $userid already exists)
        1 for unique (i.e. this $userid does not exist, or this $useri
+d/$borrowernumber combination already exists)

=cut
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