[pirsddd]

Код:

function PosF(const Sub, Str: string; From: Cardinal): Cardinal;
var
  P: PChar;
begin
  if From <= Length(Str) then
    begin
    P := StrPos(PChar(Str) + From - 1, PChar(Sub));
    if P <> nil then
      Result := P - PChar(Str) + 1
    else
      Result := 0;
    end
  else
    Result := 0;
end;

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