@@ -184,9 +184,9 @@
 		override Value eval_( Let e, Table ctx, bool ctxMod )
 		{
 			if( !ctxMod )
 				ctx = new Table(ctx, Table.Kind.NotPropagateSet);
-			Value ri = this.eval(e.init, ctx);
+			Value ri = this.eval(e.vdef, ctx);
 			ctx.set(e.name, e.layer.empty ? layerID(): e.layer, ri);
 			return this.eval(e.expr, ctx, OverwriteCtx);
 		}
 		override Value eval_( App e, Table ctx, bool ctxMod )
@@ -202,9 +202,9 @@
 		{
 			// incremental execution of let-expressions
 			if(auto le = cast(Let)e)
 			{
-				AST ai = runMacro(le.init, ctx);
+				AST ai = runMacro(le.vdef, ctx);
 
 				if( !ctxMod )
 					ctx = new Table(ctx, Table.Kind.NotPropagateSet);
 
@@ -242,9 +242,14 @@
 		override Value eval_( Var e, Table ctx, bool ctxMod )
 		{
 			if( ctx.has(e.name, layerID()) )
 				return ctx.get(e.name, layerID());
-			return this.lift(ctx.get(e.name, ValueLayer, e.pos), ctx, e.pos);
+			Value v;
+			try { v = ctx.get(e.name, ValueLayer, e.pos); }
+			catch ( RuntimeException ) {
+				throw genex!RuntimeException(e.pos, e.name~" not found in layer "~layerID()~" nor "~ValueLayer);
+			}
+			return this.lift(v, ctx, e.pos);
 		}
 	}
 
 	// Macro layer. For optimization, if AST didn't change it returns null
@@ -285,18 +290,18 @@
 		{
 			if( !ctxMod )
 				ctx = new Table(ctx, Table.Kind.NotPropagateSet);
 
-			Value ai = this.eval(e.init, ctx);
+			Value ai = this.eval(e.vdef, ctx);
 			ctx.set(e.name, NoopLayer, null);
 			Value ae = this.eval(e.expr, ctx, OverwriteCtx);
 
 			if( ai is null && ae is null ) return null;
-			if( ai is null ) ai = ast2table(e.init);
+			if( ai is null ) ai = ast2table(e.vdef);
 			if( ae is null ) ae = ast2table(e.expr);
 
 			return ast2table(e, delegate Value (AST _){
-				if(_ is e.init) { return ai; }
+				if(_ is e.vdef) { return ai; }
 				if(_ is e.expr) { return ae; }
 				assert(false);
 			});
 		}