--- a/mde/content/AStringContent.d	Tue Jan 06 16:54:04 2009 +0000
+++ b/mde/content/AStringContent.d	Thu Jan 08 13:05:44 2009 +0000
@@ -154,6 +154,10 @@
 	assignNoCb (val);
 	super (symbol);
     }
+    // for use by EnumValueContent
+    protected this (char[] symbol, int dummy) {
+        super (symbol);
+    }
     
     void assignNoCb (bool val) {
 	v = val;
@@ -289,7 +293,6 @@
 /** A content representing an enumeration.
  *
  * Extends IntContent for Options support. */
-// maybe avoid problems by adding a special callback to BoolContent subclass?
 class EnumContent : IntContent, IContentList
 {
     /** CTOR.
@@ -300,29 +303,32 @@
     */
     this (char[] symbol, char[][] enumSymbols, int val = 0) {
         enums.length = enumSymbols.length;
+        char[] symPeriod = symbol~'.';
         foreach (i, ref e; enums) {
-            e = new BoolContent (enumSymbols[i], false);
-            e.addCallback (&enumAssignCb);
+            e = new EnumValueContent (this, i, symPeriod~enumSymbols[i]);
         }
-	super (symbol, val);
-        //NOTE: if val is 0, no enumeration should be set; however it seems to work!
+        super (symbol, val);	// calls assignNoCb
     }
     
-    override void assignNoCb (int val) {
-        if (val == v) return;
+    override void assignNoCb (int val) {	// called by children (via opAssign)
         if (val >= enums.length || val < 0) {
 	    logger.error ("EnumContent "~name_~" assigned invalid value; keeping value: "~sv);
 	    return;
 	}
-        enums[v] = false;
-        enums[val] = true;
+        enums[v]  .assignFromParent (false);
+        enums[val].assignFromParent (true);
 	v = val;
-        svAssign;
+        sv = enums[v].name_;
+        if (pos > sv.length) pos = sv.length;
+        endEvent;
     }
-    void svAssign () {
-	sv = enums[v].name_;
-	if (pos > sv.length) pos = sv.length;
-        endEvent;
+    // Change if true, assert current value if false
+    void childAssign (int val) {
+        debug assert (0 <= val && val < enums.length, "cA out of bounds");
+        if (enums[val].v)
+            assignNoCb (val);
+        else
+            enums[val].assignFromParent (v == val);
     }
     
     override char[] endEdit () {
@@ -346,19 +352,35 @@
     }
     
 protected:
-    void enumAssignCb (Content c) {
-        if (enums[v] is c) {	// No other is set so persist value
-            enums[v].assignNoCb (true);
+    EnumValueContent[] enums;
+    
+    /** Special version of BoolContent for each enumeration to update the parent Enum. */
+    private class EnumValueContent : BoolContent {
+        /** New enumeration of parent with index num. */
+        this (EnumContent parent, size_t num, char[] symbol) {
+            this.parent = parent;
+            i = num;
+            super (symbol, 0);	// parent sets value (if true); we shouldn't
+            sv = "false";	// except for this
+        }
+        
+        override void assignNoCb (bool val) {
+            v = val;
+            parent.childAssign (i);
         }
-        foreach (i,e; enums)
-            if (c is e) {
-            	enums[v].assignNoCb = false;	// NOTE: opAssign causes sigsegv (due to recursive calling?)
-                v = i;
-                svAssign;
-                return;
-            }
-        debug logger.error ("EnumContent.enumAssignCb: invalid value (code error)");
+        void assignFromParent (bool val) {	// don't call back to parent
+            super.assignNoCb (val);
+            endEvent;
+        }
+        
+        override char[] endEdit () {
+            v = sv && (sv[0] == 't' || sv[0] == 'T' || sv[0] == '1');
+            parent.childAssign (i);
+            return sv;
+        }
+    
+    protected:
+        EnumContent parent;
+        size_t i;
     }
-    
-    BoolContent[] enums;	// NOTE: an array isn't always fastest
 }