Membuat Fungsi Terbilang dengan Delphi

Hello gan's, nih kode program dalam bahasa delphi untuk melakukan fungsi terbilang, misalnya, gan's menginput nilai 1000 maka akan menghasilkan Seribu.
Kompilasi sebagai unit untuk kemudian di include (uses) dalam program utama.
Syntax penggunaan dengan memanggil fungsi : bilang(val:string):string.
Digit maksimal adalah 15 digit.

unit terbilang;
interface
uses
  SysUtils,StrUtils;
function bilang(const val:string):String;
function split(const val:string):string;
const
  kata : array[0..9]of string = ('Nol','Satu','Dua','Tiga','Empat','Lima','Enam','Tujuh','Delapan','Sembilan');
  max_len : integer = 15;
implementation
function bilang(const val:string):String;
var
  s,a : string;
  out : string;
begin
  s := val;
  if LeftStr(s,1) = '-' then begin
    out := 'Minus ';
    s := RightStr(s,length(s)-1);
  end else out := '';
  if Length(s) > max_len then begin
    Result := 'OVER LIMIT !!!';
    Exit;
  end;
  if Length(s) > 12 then begin  //trilyun
    a := MidStr(s,1,Length(s)-12);
    out := split(a) + ' Trilyun ';
    s := RightStr(s,length(s)-length(a));
  end;
  if Length(s) > 9 then begin  //milyar
    a := MidStr(s,1,length(s)-9);
    out := out + split(a) + ' Milyar ';
    s := RightStr(s,length(s)-length(a));
  end;
  if Length(s) > 6 then begin //juta
    a := MidStr(s,1,length(s)-6);
    out := out + split(a) + ' Juta ';
    s := RightStr(s,length(s)-length(a));
  end;
  if Length(s) > 3 then begin //ribu
    a := MidStr(s,1,length(s)-3);
    if StrToInt(a)=1 then
      out := out + ' Seribu '
    else if StrToInt(a)<>0 then out := out + split(a) + ' Ribu ';
    s := RightStr(s,length(s)-length(a));
  end;
  out := out + split(s);
  Result := Trim(StringReplace(out,'  ',' ',[rfReplaceAll]));
end;
function split(const val:string):string;
var
  i,i2 : integer;
  s,out : string;
begin
  s := val;
  out := '';
  if length(s) = 3 then begin
    i := StrToInt(LeftStr(s,1));
    if i = 1 then
      out := ' Seratus '
    else if (i>1) then
      out := kata[i] + ' Ratus ';
    s := RightStr(s,2);
  end;
  if length(s) = 2 then begin
    i := StrToInt(LeftStr(s,1));
    i2 := StrToInt(RightStr(s,1));
    if (i=1) and (i2=0) then
      out := out + ' Sepuluh '
    else if (i=1) and (i2=1) then
      out := out + ' Sebelas '
    else if (i>1) and (i2=0) then
      out := out + kata[i] + ' Puluh '
    else if (i=1) and (i2>0) then
      out := out + kata[i2] + ' Belas '
    else if (i<>0) and (i2<>0) then
      out := out + kata[i] + ' Puluh ' + kata[i2]
    else if (i=0) and (i2<>0) then
      out := out + kata[i2];
  end;
  if Length(s) = 1 then out := out + kata[StrToInt(s)];

  Result := out;
end;
end.

 Semoga saja berfungsi codingnya. :D