正则表达式在每行开头插入行号

var
  Rgr: TRegExpr;
  i: Integer;
begin
  i := 0;
  Memo1.Lines.Clear;
  Memo1.Lines.LoadFromFile('d:\a1.txt');
  Memo2.Lines.Clear;
  Rgr := TRegExpr.Create;
  Rgr.ModifierM := True;
  Rgr.Expression := '(^\w+[^.])';
  try
    if Rgr.Exec(Memo1.Text) then
      repeat
        i := i + 1;
        memo2.Lines.Add(Format('%d.  ', [i]) + Rgr.Match[1]);
      until not Rgr.ExecNext;
  finally
    Rgr.Free;
  end;
end;