--- a/src/luan/LuanJavaFunction.java	Thu May 22 14:29:11 2025 -0600
+++ b/src/luan/LuanJavaFunction.java	Thu May 22 19:04:23 2025 -0600
@@ -11,9 +11,13 @@
 import java.util.Set;
 import java.util.Arrays;
 import java.util.Collection;
+import goodjava.logging.Logger;
+import goodjava.logging.LoggerFactory;
 
 
 public final class LuanJavaFunction extends LuanFunction {
+	private static final Logger logger = LoggerFactory.getLogger(LuanJavaFunction.class);
+
 	private final JavaMethod method;
 	private Object obj;
 	private final RtnConverter rtnConverter;
@@ -99,6 +103,8 @@
 				throw (Error)cause;
 			if( cause instanceof LuanException )
 				throw (LuanException)cause;
+			if( cause instanceof LuanRuntimeException )
+				throw ((LuanRuntimeException)cause).luanException;
 			throw new LuanException(cause);
 		} catch(InstantiationException e) {
 			throw new RuntimeException(e);

--- a/src/luan/LuanRuntimeException.java	Thu May 22 14:29:11 2025 -0600
+++ b/src/luan/LuanRuntimeException.java	Thu May 22 19:04:23 2025 -0600
@@ -5,8 +5,11 @@
 
 
 public final class LuanRuntimeException extends RuntimeException {
+	public final LuanException luanException;
+
 	public LuanRuntimeException(LuanException e) {
 		super(e);
+		luanException = e;
 	}
 
 	@Override public void printStackTrace(PrintStream s) {

--- a/src/luan/modules/swing/SwingLuan.java	Thu May 22 14:29:11 2025 -0600
+++ b/src/luan/modules/swing/SwingLuan.java	Thu May 22 19:04:23 2025 -0600
@@ -52,6 +52,8 @@
 					fn.call(luan);
 				} catch(LuanException e) {
 					exception(e);
+				} catch(LuanRuntimeException e) {
+					exception(e.luanException);
 				}
 			}
 		};

--- a/src/luan/modules/swing/TextAreaLineNumbersLuan.java	Thu May 22 14:29:11 2025 -0600
+++ b/src/luan/modules/swing/TextAreaLineNumbersLuan.java	Thu May 22 19:04:23 2025 -0600
@@ -22,6 +22,8 @@
 import javax.swing.border.EmptyBorder;
 import goodjava.logging.Logger;
 import goodjava.logging.LoggerFactory;
+import luan.LuanException;
+import luan.LuanRuntimeException;
 
 
 public class TextAreaLineNumbersLuan extends JComponent implements DocumentUpdateListener {
@@ -39,16 +41,14 @@
 	}
 
 	private final TextAreaLuan textArea;
-	private int currentLine = -1;
+	private int lines;
 	private int height;
 	private int lineStartSelection = -1;
 	private final LuanDocumentListener ldl = new LuanDocumentListener(this);
 
 	public TextAreaLineNumbersLuan(TextAreaLuan textArea) {
-		Insets textInsets = textArea.getInsets();
-		Border border = new EmptyBorder(textInsets.top,0,textInsets.bottom,0);
-		setBorder(border);
 		this.textArea = textArea;
+		this.lines = textArea.getLineCount();
 		//logger.info("lines "+lines);
 		setFont(textArea.getFont());
 		textArea.getDocument().addDocumentListener(new WeakDocumentListener(ldl));
@@ -57,9 +57,8 @@
 	}
 
 	@Override public void setBorder(Border border) {
-		Insets borderInsets = ((EmptyBorder)border).getBorderInsets();
-		Insets insets = getInsets();
-		border = new EmptyBorder(insets.top,borderInsets.left,insets.bottom,borderInsets.right);
+		if( !border.getClass().equals(EmptyBorder.class) )
+			throw new LuanRuntimeException(new LuanException("border must be EmptyBorder"));
 		super.setBorder(border);
 	}
 
@@ -79,12 +78,16 @@
 	@Override public Dimension getPreferredSize() {
 		//logger.info("getPreferredSize");
 		int height = getInnerHeight();
-		int lines = textArea.getLineCount();
 		int width = getFontMetrics(getFont()).stringWidth(intToString(lines));
 		//logger.info("lines = "+lines);
 		//logger.info("height = "+height);
+		Insets textInsets = textArea.getInsets();
 		Insets insets = getInsets();
-		height += insets.top + insets.bottom;
+		if( textInsets.top != insets.top || textInsets.bottom != insets.bottom ) {
+			Border border = new EmptyBorder(textInsets.top,insets.left,textInsets.bottom,insets.right);
+			setBorder(border);
+		}
+		height += textInsets.top + textInsets.bottom;
 		width += insets.left + insets.right;
 		return new Dimension(width, height);
 	}
@@ -93,7 +96,6 @@
 		//logger.info("paintComponent");
 		super.paintComponent(g);
 		FontMetrics fm = g.getFontMetrics();
-		int lines = textArea.getLineCount();
 		int xRight = getInsets().left + fm.stringWidth(intToString(lines));
 		try {
 			for( int i = 0; i < lines; i++ ) {
@@ -110,24 +112,26 @@
 	}
 
 	@Override public void updated(final DocumentEvent event) {
+		final int oldLine = lines;
+		lines = textArea.getLineCount();
 		SwingUtilities.invokeLater(new Runnable(){public void run(){
 			//logger.info(event.getType().toString()+" "+event.getOffset()+" "+event.getLength());
-			try {
-				int startOffset = event.getOffset();
-				int startLine = textArea.getLineOfOffset(startOffset);
-				int endOffset = startOffset + event.getLength();
-				endOffset = Math.min( endOffset, textArea.getText().length() );
-				int endLine = textArea.getLineOfOffset(endOffset);
-				//logger.info("lines "+startLine+" to "+endLine);
-				if( startLine == endLine ) {
-					if( currentLine == startLine && height == getInnerHeight() )
-						return;
-					currentLine = startLine;
-				} else {
-					currentLine = -1;
+			if( oldLine == lines ) {
+				try {
+					int startOffset = event.getOffset();
+					int startLine = textArea.getLineOfOffset(startOffset);
+					int endOffset = startOffset + event.getLength();
+					endOffset = Math.min( endOffset, textArea.getText().length() );
+					int endLine = textArea.getLineOfOffset(endOffset);
+					//logger.info("lines "+startLine+" to "+endLine);
+					if( startLine == endLine ) {
+						int height = TextAreaLineNumbersLuan.this.height;
+						if( height == getInnerHeight() )
+							return;
+					}
+				} catch(BadLocationException e) {
+					throw new RuntimeException(e);
 				}
-			} catch(BadLocationException e) {
-				throw new RuntimeException(e);
 			}
 			revalidate();
 			repaint();