--- a/dwt/custom/StyledText.d	Sun Jun 08 15:11:48 2008 +0200
+++ b/dwt/custom/StyledText.d	Sun Jun 15 22:32:20 2008 +0200
@@ -1598,15 +1598,13 @@
  *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
  *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
  * </ul>
- * @exception IllegalArgumentException <ul>
- *    <li>ERROR_NULL_ARGUMENT when listener is null</li>
- * </ul>
  */
 public void append(String string) {
     checkWidget();
-    if (string is null) {
-        DWT.error(DWT.ERROR_NULL_ARGUMENT);
-    }
+    // DWT extension: allow null for zero length string
+//     if (string is null) {
+//         DWT.error(DWT.ERROR_NULL_ARGUMENT);
+//     }
     int lastChar = Math.max(getCharCount(), 0);
     replaceTextRange(lastChar, 0, string);
 }
@@ -4934,15 +4932,13 @@
  *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
  *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
  * </ul>
- * @exception IllegalArgumentException <ul>
- *    <li>ERROR_NULL_ARGUMENT when string is null</li>
- * </ul>
  */
 public void insert(String string) {
     checkWidget();
-    if (string is null) {
-        DWT.error(DWT.ERROR_NULL_ARGUMENT);
-    }
+    // DWT extension: allow null for zero length string
+//     if (string is null) {
+//         DWT.error(DWT.ERROR_NULL_ARGUMENT);
+//     }
     Point sel = getSelectionRange();
     replaceTextRange(sel.x, sel.y, string);
 }
@@ -6457,7 +6453,6 @@
  * </ul>
  * @exception IllegalArgumentException <ul>
  *   <li>ERROR_INVALID_RANGE when either start or end is outside the valid range (0 <= offset <= getCharCount())</li>
- *   <li>ERROR_NULL_ARGUMENT when ranges is null</li>
  * </ul>
  *
  * @since 2.0
@@ -6467,7 +6462,8 @@
 public void replaceStyleRanges(int start, int length, StyleRange[] ranges) {
     checkWidget();
     if (isListening(LineGetStyle)) return;
-    if (ranges is null) DWT.error(DWT.ERROR_NULL_ARGUMENT);
+    // DWT extension: allow null for zero length string
+    //if (ranges is null) DWT.error(DWT.ERROR_NULL_ARGUMENT);
     setStyleRanges(start, length, null, ranges, false);
 }
 /**
@@ -6500,14 +6496,14 @@
  *   <li>ERROR_INVALID_RANGE when either start or end is outside the valid range (0 <= offset <= getCharCount())</li>
  *   <li>ERROR_INVALID_ARGUMENT when either start or end is inside a multi byte line delimiter.
  *      Splitting a line delimiter for example by inserting text in between the CR and LF and deleting part of a line delimiter is not supported</li>
- *   <li>ERROR_NULL_ARGUMENT when string is null</li>
  * </ul>
  */
 public void replaceTextRange(int start, int length, String text) {
     checkWidget();
-    if (text is null) {
-        DWT.error(DWT.ERROR_NULL_ARGUMENT);
-    }
+    // DWT extension: allow null for zero length string
+//     if (text is null) {
+//         DWT.error(DWT.ERROR_NULL_ARGUMENT);
+//     }
     int contentLength = getCharCount();
     int end = start + length;
     if (start > end || start < 0 || end > contentLength) {
@@ -8095,7 +8091,6 @@
  *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
  * </ul>
  * @exception IllegalArgumentException <ul>
- *    <li>ERROR_NULL_ARGUMENT when the list of ranges is null</li>
  *    <li>ERROR_INVALID_RANGE when the last of the style ranges is outside the valid range (> getCharCount())</li>
  * </ul>
  *
@@ -8104,7 +8099,8 @@
 public void setStyleRanges(StyleRange[] ranges) {
     checkWidget();
     if (isListening(LineGetStyle)) return;
-    if (ranges is null) DWT.error(DWT.ERROR_NULL_ARGUMENT);
+    // DWT extension: allow null for zero length string
+    //if (ranges is null) DWT.error(DWT.ERROR_NULL_ARGUMENT);
     setStyleRanges(0, 0, null, ranges, true);
 }
 /**
@@ -8142,15 +8138,13 @@
  *    <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li>
  *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li>
  * </ul>
- * @exception IllegalArgumentException <ul>
- *    <li>ERROR_NULL_ARGUMENT when string is null</li>
- * </ul>
  */
 public void setText(String text) {
     checkWidget();
-    if (text is null) {
-        DWT.error(DWT.ERROR_NULL_ARGUMENT);
-    }
+    // DWT extension: allow null for zero length string
+//     if (text is null) {
+//         DWT.error(DWT.ERROR_NULL_ARGUMENT);
+//     }
     Event event = new Event();
     event.start = 0;
     event.end = getCharCount();