diff --git a/folder-alias.json b/folder-alias.json
new file mode 100644
index 0000000..9e26dfe
--- /dev/null
+++ b/folder-alias.json
@@ -0,0 +1 @@
+{}
\ No newline at end of file
diff --git a/hscript/Checker.hx b/hscript/Checker.hx
index 800f755..ca7ed9e 100644
--- a/hscript/Checker.hx
+++ b/hscript/Checker.hx
@@ -1078,7 +1078,7 @@ class Checker {
 				return et;
 			default:
 			}
-		case EFor(v, it, e):
+		case EFor(k, v, it, e):
 			var locals = saveLocals();
 			var itt = typeExpr(it, Value);
 			var vt = switch( follow(itt) ) {
diff --git a/hscript/Expr.hx b/hscript/Expr.hx
index 62862ee..47da73e 100644
--- a/hscript/Expr.hx
+++ b/hscript/Expr.hx
@@ -54,7 +54,7 @@ enum Expr {
 	ECall( e : Expr, params : Array<Expr> );
 	EIf( cond : Expr, e1 : Expr, ?e2 : Expr );
 	EWhile( cond : Expr, e : Expr );
-	EFor( v : String, it : Expr, e : Expr );
+	EFor( k : String, v : String, it : Expr, e : Expr );
 	EBreak;
 	EContinue;
 	EFunction( args : Array<Argument>, e : Expr, ?name : String, ?ret : CType );
@@ -115,6 +115,7 @@ enum Error {
 	EInvalidPreprocessor( msg : String );
 	EUnknownVariable( v : String );
 	EInvalidIterator( v : String );
+	EInvalidKeyValueIterator( v : String );
 	EInvalidOp( op : String );
 	EInvalidAccess( f : String );
 	ECustom( msg : String );
diff --git a/hscript/Interp.hx b/hscript/Interp.hx
index 890c913..22d837d 100644
--- a/hscript/Interp.hx
+++ b/hscript/Interp.hx
@@ -172,6 +172,7 @@ class Interp {
 						if (Type.typeof(scriptObject) == TObject) {
 							Reflect.setField(scriptObject, id, v);
 						} else {
+							#if !web
 							if (__instanceFields.contains(id)) {
 								Reflect.setProperty(scriptObject, id, v);
 							} else if (__instanceFields.contains('set_$id')) { // setter
@@ -179,6 +180,13 @@ class Interp {
 							} else {
 								setVar(id, v);
 							}
+							#else
+							try {
+								Reflect.setProperty(scriptObject, id, v);
+							} catch(e) {
+								setVar(id, v);
+							}
+							#end
 						}
 					} else {
 						setVar(id, v);
@@ -219,6 +227,7 @@ class Interp {
 				var l = locals.get(id);
 				v = fop(expr(e1), expr(e2));
 				if (l == null) {
+					#if !web
 					if (__instanceFields.contains(id)) {
 						Reflect.setProperty(scriptObject, id, v);
 					} else if (__instanceFields.contains('set_$id')) { // setter
@@ -226,6 +235,13 @@ class Interp {
 					} else {
 						setVar(id, v);
 					}
+					#else
+					try {
+						Reflect.setProperty(scriptObject, id, v);
+					} catch(e) {
+						setVar(id, v);
+					}
+					#end
 				}
 				else
 					l.r = v;
@@ -330,7 +346,7 @@ class Interp {
 					return v;
 			}
 		} catch(e) {
-			error(ECustom('${e.toString()}'));
+			error(ECustom('${Std.string(e)}'));
 		}
 		return null;
 	}
@@ -510,8 +526,8 @@ class Interp {
 			case EDoWhile(econd, e):
 				doWhileLoop(econd, e);
 				return null;
-			case EFor(v, it, e):
-				forLoop(v, it, e);
+			case EFor(k, v, it, e):
+				forLoop(k, v, it, e);
 				return null;
 			case EBreak:
 				throw SBreak;
@@ -751,24 +767,47 @@ class Interp {
 
 	function makeIterator(v:Dynamic):Iterator<Dynamic> {
 		#if ((flash && !flash9) || (php && !php7 && haxe_ver < '4.0.0'))
-		if (v.iterator != null)
-			v = v.iterator();
+		if (v.keyValueIterator != null)
+			v = v.keyValueIterator();
 		#else
 		try
-			v = v.iterator()
+			v = v.keyValueIterator()
 		catch (e:Dynamic) {};
 		#end
+		if (v.hasNext == null || v.next == null) {
+			#if ((flash && !flash9) || (php && !php7 && haxe_ver < '4.0.0'))
+			if (v.iterator != null)
+				v = v.iterator();
+			#else
+			try
+				v = v.iterator()
+			catch (e:Dynamic) {};
+			#end
+		}
 		if (v.hasNext == null || v.next == null)
 			error(EInvalidIterator(v));
 		return v;
 	}
 
-	function forLoop(n, it, e) {
+	function forLoop(k, n, it, e) {
 		var old = declared.length;
+		if (k != null) declared.push({n: k, old: locals.get(k), depth: depth});
 		declared.push({n: n, old: locals.get(n), depth: depth});
 		var it = makeIterator(expr(it));
 		while (it.hasNext()) {
-			locals.set(n, {r: it.next(), depth: depth});
+			var next = it.next();
+
+			if (k != null) {
+				if (next != null && next is Dynamic && Reflect.hasField(next, "key") && Reflect.hasField(next, "value")) {
+					trace("is key iterator");
+					locals.set(k, {r: next.key, depth: depth});
+					locals.set(n, {r: next.value, depth: depth});
+				} else {
+					error(EInvalidKeyValueIterator(Std.string(it)));
+					return;
+				}
+			} else
+				locals.set(n, {r: next, depth: depth});
 			try {
 				expr(e);
 			} catch (err:Stop) {
@@ -796,8 +835,8 @@ class Interp {
 		cast(map, haxe.Constraints.IMap<Dynamic, Dynamic>).set(key, value);
 	}
 
-	public static var getRedirects:Map<String, Dynamic->String->Dynamic> = [];
-	public static var setRedirects:Map<String, Dynamic->String->Dynamic->Dynamic> = [];
+	public static var getRedirects:Map<String, (Dynamic->String->Dynamic)> = [];
+	public static var setRedirects:Map<String, (Dynamic->String->Dynamic->Dynamic)> = [];
 
 	function get(o:Dynamic, f:String):Dynamic {
 		if (o == null)
@@ -816,12 +855,13 @@ class Interp {
 				case _:
 					null;
 			};
-			if (getRedirects.exists(cl = Type.getClassName(Type.getClass(o))) && (redirect = getRedirects[cl]) != null) {
+			var cla = Type.getClass(o);
+			if (cla != null && getRedirects.exists(cl = Type.getClassName(cla)) && (redirect = getRedirects[cl]) != null) {
 				return redirect(o, f);
 			} else {
 				var v = null;
-				if ((v = Reflect.getProperty(o, f)) == null)
-					v = Reflect.getProperty(Type.getClass(o), f);
+				if ((v = Reflect.getProperty(o, f)) == null && cla != null)
+					v = Reflect.getProperty(cla, f);
 				return v;
 			}
 		}
@@ -844,7 +884,8 @@ class Interp {
 			case _:
 				null;
 		};
-		if (setRedirects.exists(cl = Type.getClassName(Type.getClass(o))) && (redirect = setRedirects[cl]) != null)
+		var cla = Type.getClass(o);
+		if (cla != null && setRedirects.exists(cl = Type.getClassName(cla)) && (redirect = setRedirects[cl]) != null)
 			return redirect(o, f, v);
 
 		Reflect.setProperty(o, f, v);
diff --git a/hscript/Macro.hx b/hscript/Macro.hx
index c9cc6c1..5c95db2 100644
--- a/hscript/Macro.hx
+++ b/hscript/Macro.hx
@@ -196,7 +196,7 @@ class Macro {
 				EWhile(convert(c), convert(e), true);
 			case EDoWhile(c, e):
 				EWhile(convert(c), convert(e), false);
-			case EFor(v, it, efor):
+			case EFor(k, v, it, efor):
 				#if (haxe_ver >= 4)
 					var p = #if hscriptPos { file : p.file, min : e.pmin, max : e.pmax } #else p #end;
 					EFor({ expr : EBinop(OpIn,{ expr : EConst(CIdent(v)), pos : p },convert(it)), pos : p }, convert(efor));
diff --git a/hscript/Parser.hx b/hscript/Parser.hx
index 2f1e646..35eeb1a 100644
--- a/hscript/Parser.hx
+++ b/hscript/Parser.hx
@@ -283,7 +283,7 @@ class Parser {
 		case EUnop(_,prefix,e): !prefix && isBlock(e);
 		case EWhile(_,e): isBlock(e);
 		case EDoWhile(_,e): isBlock(e);
-		case EFor(_,_,e): isBlock(e);
+		case EFor(_,_,_,e): isBlock(e);
 		case EReturn(e): e != null && isBlock(e);
 		case ETry(_, _, _, e): isBlock(e);
 		case EMeta(_, _, e): isBlock(e);
@@ -534,8 +534,8 @@ class Parser {
 	function mapCompr( tmp : String, e : Expr ) {
 		if( e == null ) return null;
 		var edef = switch( expr(e) ) {
-		case EFor(v, it, e2):
-			EFor(v, it, mapCompr(tmp, e2));
+		case EFor(k, v, it, e2):
+			EFor(k, v, it, mapCompr(tmp, e2));
 		case EWhile(cond, e2):
 			EWhile(cond, mapCompr(tmp, e2));
 		case EDoWhile(cond, e2):
@@ -636,11 +636,22 @@ class Parser {
 		case "for":
 			ensure(TPOpen);
 			var vname = getIdent();
-			ensureToken(TId("in"));
+			var key:String = null;
+			var tk = token();
+			switch(tk) {
+				case TOp("=>"):
+					key = vname;
+					vname = getIdent();
+					ensureToken(TId("in"));
+				case TId("in"):
+
+				default:
+					unexpected(tk);
+			}
 			var eiter = parseExpr();
 			ensure(TPClose);
 			var e = parseExpr();
-			mk(EFor(vname,eiter,e),p1,pmax(e));
+			mk(EFor(key, vname,eiter,e),p1,pmax(e));
 		case "break": mk(EBreak);
 		case "continue": mk(EContinue);
 		case "else": unexpected(TId(id));
diff --git a/hscript/Printer.hx b/hscript/Printer.hx
index d9972d1..0ec792f 100644
--- a/hscript/Printer.hx
+++ b/hscript/Printer.hx
@@ -200,8 +200,11 @@ class Printer {
 			add(" while ( ");
 			expr(cond);
 			add(" )");
-		case EFor(v, it, e):
-			add("for( "+v+" in ");
+		case EFor(k, v, it, e):
+			if (k != null)
+				add('for($k=>$v in ');
+			else 
+				add('for($v in ');
 			expr(it);
 			add(" ) ");
 			expr(e);
@@ -340,6 +343,7 @@ class Printer {
 			case EInvalidPreprocessor(str): "Invalid preprocessor (" + str + ")";
 			case EUnknownVariable(v): "Unknown variable: "+v;
 			case EInvalidIterator(v): "Invalid iterator: "+v;
+			case EInvalidKeyValueIterator(v): "Invalid key-value iterator: "+v;
 			case EInvalidOp(op): "Invalid operator: "+op;
 			case EInvalidAccess(f): "Invalid access to field " + f;
 			case ECustom(msg): msg;
diff --git a/hscript/Tools.hx b/hscript/Tools.hx
index 64562f2..1c1d737 100644
--- a/hscript/Tools.hx
+++ b/hscript/Tools.hx
@@ -38,7 +38,7 @@ class Tools {
 		case EIf(c, e1, e2): f(c); f(e1); if( e2 != null ) f(e2);
 		case EWhile(c, e): f(c); f(e);
 		case EDoWhile(c, e): f(c); f(e);
-		case EFor(_, it, e): f(it); f(e);
+		case EFor(_, _, it, e): f(it); f(e);
 		case EBreak,EContinue:
 		case EFunction(_, e, _, _): f(e);
 		case EReturn(e): if( e != null ) f(e);
@@ -75,7 +75,7 @@ class Tools {
 		case EIf(c, e1, e2): EIf(f(c),f(e1),if( e2 != null ) f(e2) else null);
 		case EWhile(c, e): EWhile(f(c),f(e));
 		case EDoWhile(c, e): EDoWhile(f(c),f(e));
-		case EFor(v, it, e): EFor(v, f(it), f(e));
+		case EFor(k, v, it, e): EFor(k, v, f(it), f(e));
 		case EFunction(args, e, name, t): EFunction(args, f(e), name, t);
 		case EReturn(e): EReturn(if( e != null ) f(e) else null);
 		case EArray(e, i): EArray(f(e),f(i));