Smart pascal source code


type
  TMyFunc = function(i: Integer): String;

type
  TMyClass = class
    FEvent: TMyFunc;
    function DoConv(i: Integer): String;
  end;

function TMyClass.DoConv(i: Integer): String;
begin
  Result := '[' + IntToStr(i) + ']';
end;

var
o := TMyClass.Create;

if Assigned(o.FEvent) then
  WriteLn(o.FEvent(1))
else
  WriteLn('Unassigned');
o.FEvent := o.DoConv;
if Assigned(o.FEvent) then
  WriteLn(o.FEvent(2));

var e: TMyFunc;

if Assigned(e) then
  WriteLn(e(3))
else
  WriteLn('Unassigned');
e := o.DoConv;
if Assigned(e) then
  WriteLn(e(4));

e := nil;
o.FEvent := e;

if Assigned(e) then
  WriteLn(e(5))
else
  WriteLn('Unassigned');

{<<< RESULT - CONSOLE LOG >>>
-----------------------------
Unassigned
[2]
Unassigned
[4]
Unassigned
-----------------------------
{<<<<<<<<< THE END >>>>>>>>>}

var TObject={
	$ClassName: "TObject",
	$Parent: null,
	ClassName: function (s) { return s.$ClassName },
	ClassType: function (s) { return s },
	ClassParent: function (s) { return s.$Parent },
	$Init: function () {},
	Create: function (s) { return s },
	Destroy: function (s) { for (var prop in s) if (s.hasOwnProperty(prop)) delete s.prop },
	Destroy$: function(s) { return s.ClassType.Destroy(s) },
	Free: function (s) { if (s!==null) s.ClassType.Destroy(s) }
}
var Exception={
	$ClassName: "Exception",
	$Parent: TObject,
	$Init: function () { FMessage="" },
	Create: function (s,Msg) { s.FMessage=Msg; return s }
}
function $New(c) { var i={ClassType:c}; c.$Init(i); return i }
function $Event1(i,f) {
	var li=i,lf=f;
	return function(a) {
		return lf.call(li,li,a)
	}
}
function $CheckFunc(i,z) { if (i) return i; throw Exception.Create($New(Exception),"Function pointer is nil"+z); }
function $Check(i,z) { if (i) return i; throw Exception.Create($New(Exception),"Object not instantiated"+z); }
function WriteLn(value) {
    if (window.console) { window.console.log(value); } };
var TMyClass = {
   $ClassName:"TMyClass",$Parent:TObject
   ,$Init:function ($) {
      TObject.$Init($);
      $.FEvent = null;
   }
   ,DoConv:function(Self, i) {
      return "["+i.toString()+"]";
   }
   ,Destroy:TObject.Destroy
};
var o = null,
   e = null;

/* <<< main JS >>> */

   o = TObject.Create($New(TMyClass));
   if ($Check(o,"").FEvent) {
      WriteLn($CheckFunc($Check(o,"").FEvent,"")(1));
   } else {
      WriteLn("Unassigned");
   }
   $Check(o,"").FEvent = $Event1(o,TMyClass.DoConv);
   if ($Check(o,"").FEvent) {
      WriteLn($CheckFunc($Check(o,"").FEvent,"")(2));
   }
   if (e) {
      WriteLn($CheckFunc(e,"")(3));
   } else {
      WriteLn("Unassigned");
   }
   e = $Event1(o,TMyClass.DoConv);
   if (e) {
      WriteLn($CheckFunc(e,"")(4));
   }
   e = null;
   $Check(o,"").FEvent = e;
   if (e) {
      WriteLn($CheckFunc(e,"")(5));
   } else {
      WriteLn("Unassigned");
   }