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Open array parameters

The concept of open arrays allow arrays of different sizes to be passed to the same procedure or function.

function Sum(Arr: Array of Integer): Integer;
var
 i: Integer;
begin
  Result := 0;
  for i := Low(Arr) to High(Arr) do 
    Result := Result + Arr[i];
end; 

In C++ there is no counterpart to the function "High", which typically is needed to use the open array. Therefore in C++ the value of the upper bound of the open array has to be passed together with a pointer to the first element of the array.

int __fastcall Sum( const int * Arr, int Arr_high )
{
  int result;
  int i;
  result = 0;
  for ( i = 0 /* Low( Arr )*/; i <= Arr_high /* High( Arr )*/; i++)
    result = result + Arr[i];
  return result;
}