--- a/core/src/luan/LuanState.java	Wed May 27 03:20:38 2015 -0600
+++ b/core/src/luan/LuanState.java	Wed May 27 03:29:04 2015 -0600
@@ -1,5 +1,7 @@
 package luan;
 
+import java.io.Closeable;
+import java.io.IOException;
 import java.lang.ref.Reference;
 import java.lang.ref.WeakReference;
 import java.util.List;
@@ -15,7 +17,7 @@
 	final List<StackTraceElement> stackTrace = new ArrayList<StackTraceElement>();
 
 	private Map registry;
-	private final List<Reference<Runnable>> onClose = new ArrayList<Reference<Runnable>>();
+	private final List<Reference<Closeable>> onClose = new ArrayList<Reference<Closeable>>();
 
 	protected LuanState() {
 		registry = new HashMap();
@@ -35,15 +37,15 @@
 		return registry;
 	}
 
-	public void onClose(Runnable fn) {
-		onClose.add(new WeakReference<Runnable>(fn));
+	public void onClose(Closeable c) {
+		onClose.add(new WeakReference<Closeable>(c));
 	}
 
-	public void close() {
-		for( Reference<Runnable> ref : onClose ) {
-			Runnable r = ref.get();
-			if( r != null )
-				r.run();
+	public void close() throws IOException {
+		for( Reference<Closeable> ref : onClose ) {
+			Closeable c = ref.get();
+			if( c != null )
+				c.close();
 		}
 		onClose.clear();
 	}