@@ -11,17 +11,15 @@
 import polemy.ast;
 import polemy.layer;
 
 /// Parse a string and return its AST
-/// Throws: ParseException, LexException, UnexpectedEOF
 
 AST parseString(S, T...)(S str, T fn_ln_cn)
 {
 	return parserFromString(str, fn_ln_cn).parse();
 }
 
 /// Parse the content of a file and return its AST
-/// Throws: ParseException, LexException, UnexpectedEOF
 
 AST parseFile(S, T...)(S filename, T ln_cn)
 {
 	return parserFromFile(filename, ln_cn).parse();
@@ -74,18 +72,18 @@
 		///  | ["@" "@" Layer "=" Expression ([";"|"in"] Body?)?
 		///  | ["@" "@" Layer "(" Param%"," ")" "{" Body "}" ([";"|"in"] Body?)?
 
 		auto pos = currentPosition();
-		string layer = "";
-		bool layerRiseDecl = false;
+		Layer layer = "";
+		bool layerLiftDecl = false;
 
 		if( tryEat("@") )
 		{
 			layer = "@" ~ eatId("after @", AllowQuoted);
 			if( layer == "@@" )
 			{
 				layer = "@" ~ eatId("after @@", AllowQuoted);
-				layerRiseDecl = true;
+				layerLiftDecl = true;
 			}
 			else
 			{
 				if( tryEat("(") )
@@ -93,9 +91,9 @@
 			}
 		}
 
 		// [TODO] Refactor
-		if( layerRiseDecl )
+		if( layerLiftDecl )
 		{
 			string kwd = "@" ~ layer;
 			string var = layer;
 
@@ -104,9 +102,11 @@
 				: (eat("=", "after "~kwd), E(0)); // let var = ...
 			if( moreDeclarationExists() )
 				return new LetExpression(pos, var, SystemLayer, e, Body());
 			else
-				return new LetExpression(pos, var, SystemLayer, e, new VarExpression(pos, var));
+				return new LetExpression(pos, var, SystemLayer, e,
+					new LayeredExpression(pos, SystemLayer, new VarExpression(pos, var))
+				);
 		}
 		else
 		{
 			string kwd = layer;
@@ -392,9 +392,9 @@
 	}
 
 	AST doNothingExpression()
 	{
-		return new IntLiteral(currentPosition(), BigInt(178));
+		return new StrLiteral(currentPosition(), "(empty function body)");
 	}
 
 	immutable(LexPosition) currentPosition()
 	{
@@ -419,19 +419,19 @@
 	assert_eq(parseString(`def x=1`), let("x","",intl(1),var("x")));
 	assert_eq(parseString(`@val x=1;`), let("x","@val",intl(1),var("x")));
 	assert_eq(parseString(`@typ x="#int";`), let("x","@typ",strl("#int"),var("x")));
 	assert_eq(parseString(`f(1,2)`), call(var("f"),intl(1),intl(2)));
-	assert_eq(parseString(`if(1){2}`), call(var("if"),intl(1),fun([],intl(2)),fun([],intl(178))));
+	assert_eq(parseString(`if(1){2}`), call(var("if"),intl(1),fun([],intl(2)),fun([],strl("(empty function body)"))));
 	assert_eq(parseString(`if(1){2}else{3}`), call(var("if"),intl(1),fun([],intl(2)),fun([],intl(3))));
 	assert_eq(parseString(`if(1){}else{3}()()`),
-		call(call(call(var("if"),intl(1),fun([],intl(178)),fun([],intl(3))))));
+		call(call(call(var("if"),intl(1),fun([],strl("(empty function body)")),fun([],intl(3))))));
 	assert_eq(parseString(`1+2*3`), call(var("+"),intl(1),call(var("*"),intl(2),intl(3))));
 	assert_eq(parseString(`(1+2)*3`), call(var("*"),call(var("+"),intl(1),intl(2)),intl(3)));
 	assert_eq(parseString(`1*(2+3)`), call(var("*"),intl(1),call(var("+"),intl(2),intl(3))));
 	assert_eq(parseString(`1*2+3`), call(var("+"),call(var("*"),intl(1),intl(2)),intl(3)));
 	assert_eq(parseString(`@x(1)`), lay("@x", intl(1)));
 	assert_eq(parseString(`fun(x @v @t, y, z @t){}`),
-		funp([param("x",["@v","@t"]), param("y",[]), param("z",["@t"])], intl(178)));
+		funp([param("x",["@v","@t"]), param("y",[]), param("z",["@t"])], strl("(empty function body)")));
 
 	assert_eq(parseString(`
 		let x = 100; #comment
 		let y = 200; #comment!!!!!
@@ -475,9 +475,9 @@
 			var("foo"))
 	);
 
 	assert_eq(parseString(`@@type ( x ) { x }`),
-		let("@type", SystemLayer, fun(["x"], var("x")), var("@type")) );
+		let("@type", SystemLayer, fun(["x"], var("x")), lay(SystemLayer, var("@type"))) );
 
 	assert_eq(parseString(`{}`), call(var("{}")));
 	assert_eq(parseString(`{foo:1,"bar":2}`),
 		call(var(".="), call(var(".="), call(var("{}")), strl("foo"), intl(1)), strl("bar"), intl(2)));