Smart pascal source code


type
  TBase = class
  public
    palavra: string
  end;

type
  TChild = class(TBase)
  end;

//Add in Array a cast instance of type
var
  a: array of TBase;
  b: TChild;
  o: TObject;
begin  
  b := TChild.Create;
  b.palavra := 'smart';
  a.Add(b);
  a.Add(TBase(nil));
  a.Add(TBase(o));
  a.Add((o as TBase));

  Writeln(a.Length); // 4 

  var a = [], b = null;
  var o = null;

  var TBase = {
	 $ClassName:"TBase",$Parent:TObject
	 ,$Init:function ($) {
		TObject.$Init($);
		$.palavra = "";
	 }
	 ,Destroy:TObject.Destroy
  };

  var TChild = {
	 $ClassName:"TChild",$Parent:TBase
	 ,$Init:function ($) {
		TBase.$Init($);
	 }
	 ,Destroy:TObject.Destroy
  };

  b = TObject.Create($New(TChild));
  b.palavra = "smart";
  a.push(b);
  a.push($As(null,TBase));
  a.push($As(o,TBase));
  a.push($As(o,TBase));
  WriteLn(a.length); // 4 
  
/*
a = [{
		"ClassType" : {
			"$ClassName" : "TChild",
			"$Parent" : {
				"$ClassName" : "TBase",
				"$Parent" : {
					"$ClassName" : "TObject",
					"$Parent" : null
				}
			}
		},
		"palavra" : "smart"
	}, null, null, null]
*/


/*
 the compiler also has generated this piece of code 
*/

var Exception={
	$ClassName: "Exception",
	$Parent: TObject,
	$Init: function () { FMessage="" },
	Create: function (s,Msg) { s.FMessage=Msg; return s }
}

function $Is(o,c) {
	if (o===null) return false;
	return $Inh(o.ClassType,c);
}
;
function $Inh(s,c) {
	if (s===null) return false;
	while ((s)&&(s!==c)) s=s.$Parent;
	return (s)?true:false;
}
;
function $As(o,c) {
	if ((o===null)||$Is(o,c)) return o;
	throw Exception.Create($New(Exception),"Cannot cast instance of type \""+o.ClassType.$ClassName+"\" to class \""+c.$ClassName+"\"");