I can't find the error that FPC 2.6.4 is reporting

[johngalt47]

PROGRAM trimstrings;

USES   dos, strings, strutils, sysutils;

var
   InString   :   String;
   OutString   :   String;
   TempStr   : String;
   InFile      :   TextFile;
   OutFile      :   TextFile;

   N            :   integer;
   x            :   integer;

begin

   assign(InFile,'c:\eb\APP44A.eb');
   reset(InFile);

   assign(OutFile,'c:\eb\test.txt');
   rewrite(OutFile);
   OutString := 'Just a placeholder';

   while not eof(InFile) do
   begin
      readln(InFile,InString);
      If (LeftStr(Instring,1) = '{') then do <<-- FPC says there is a problem with this line
      begin
         writeln(OutFile,OutString);
         close(OutFile);
      end

=============================

Does anyone see a problem with that line?

[engkin]

Yes!

      If (LeftStr(Instring,1) = '{') then do <<-- FPC says there is a problem with this line

[christian1987]

If (LeftStr(Instring,1) = '{') then BEGIN