stack peek

Smart pascal source code


type
  TStringDynArray = array of string;

var s: TStringDynArray;

procedure DoPeek(s: TStringDynArray);
begin
  try
    WriteLn(s.Peek);
  except
    on E: Exception do
      WriteLn(E.Message);
  end;
end;

DoPeek(s);
s := ['hello', 'world'];
DoPeek(s);
s.Swap(0, 1);
DoPeek(s);
s.Delete(0);
DoPeek(s);
s.Clear;
DoPeek(s);

{<<< RESULT - CONSOLE LOG >>>
-----------------------------
Upper bound exceeded! Index 0 in DoPeek [line: 7, column: 17]
world
hello
hello
Upper bound exceeded! Index 0 in DoPeek [line: 7, column: 17]

-----------------------------
{<<<<<<<<< THE END >>>>>>>>>}

function $ArraySwap(a,i1,i2) { var t=a[i1]; a[i1]=a[i2]; a[i2]=t }
      var s = [];
      function DoPeek(s$1) {
         try {
            WriteLn($Peek(s$1,""));
         } catch ($e) {
            var E = $W($e);
            WriteLn(E.FMessage)         }
      };
      DoPeek(s);
      s = ["hello", "world"].slice();
      DoPeek(s);
      $ArraySwap(s,0,1);
      DoPeek(s);
      s.shift();
      DoPeek(s);
      s.length=0;
      DoPeek(s);
   }