diff --git a/notebook.cs b/notebook.cs
index 9c3d7cde..1ffe604a 100644
--- a/notebook.cs
+++ b/notebook.cs
@@ -36,6 +36,7 @@
           sp.setAttribute('generatedNL', '')
           bx = box s.getRangeAt(0), 'codeMainExpr', true
           bx.appendChild sp
+          makeOutputBox bx
           r = document.createRange()
           r.setStart(sp, 0)
           s.removeAllRanges()
@@ -49,12 +50,18 @@ bx.appendChild sp
 checkMutateFromModification = (b)->
   if b?
     inDef = selInDef()
-    if inDef and b.classList.contains('codeMainExpr')
-      b.classList.remove 'codeMainExpr'
-      b.classList.add 'codeMain'
-    else if !inDef and b.classList.contains('codeMain')
-      b.classList.remove 'codeMain'
-      b.classList.add 'codeMainExpr'
+    if inDef and b.classList.contains('codeMainExpr') then toDefBox b
+    else if !inDef and b.classList.contains('codeMain') then toExprBox b
+
+toExprBox = (b)->
+  b.classList.remove 'codeMain'
+  b.classList.add 'codeMainExpr'
+  makeOutputBox b
+
+toDefBox = (b)->
+  if b.output then b.parentNode.removeChild b.output
+  b.classList.remove 'codeMainExpr'
+  b.classList.add 'codeMain'
 
 selInDef = (expectedClass)->
   s = window.getSelection()
@@ -72,8 +79,7 @@ bx.appendChild sp
     s = window.getSelection()
     r = s.getRangeAt(0)
     if p = selInDef('codeMainExpr')
-      p.classList.remove 'codeMainExpr'
-      p.classList.add 'codeMain'
+      toDefBox p
 
 initNotebook = (el)->
   el.replacing = true
@@ -83,9 +89,6 @@ removeOldDefs el
     el.appendChild textNode('\n')
     el.appendChild textNode('\n')
     el.appendChild textNode('\n')
-  # bx = codeBox 'codeMain'
-  # bx.appendChild textNode('\n')
-  # el.appendChild bx
   el.normalize()
   el.replacing = false
   pgm
@@ -130,7 +133,7 @@ s.appendChild textNode('\n')
       s.setAttribute('generatedNL', '')
       bx = box main, 'codeMainExpr', true
       bx.appendChild s
-      bx.parentNode.insertBefore exprBox(bx), bx.nextSibling
+      makeOutputBox(bx)
   pgm
 
 textNode = (text)-> document.createTextNode(text)
@@ -147,15 +150,17 @@ bx.appendChild s
     exBox.lastChild.scrollIntoView()
   prompt:(msg, cont)-> cont(window.prompt(msg))
 
-exprBox = (source)->
+makeOutputBox = (source)->
   node = document.createElement 'div'
   node.setAttribute 'LeisureOutput', ''
   node.setAttribute 'Leisure', ''
   node.setAttribute 'class', 'output'
   node.setAttribute 'contentEditable', 'false'
   node.source = source
+  source.output = node
   node.innerHTML = "<button onclick='Notebook.evalOutput(this.parentNode)'>-&gt;</button>"
   node.appendChild textNode(' \n')
+  source.parentNode.insertBefore node, source.nextSibling
   node
 
 codeSpan = (text, boxType)->
diff --git a/notebook.js b/notebook.js
index 3c254483..cad1a7b1 100644
--- a/notebook.js
+++ b/notebook.js
@@ -4,7 +4,7 @@
 */
 
 (function() {
-  var Leisure, ReplCore, addsLine, bindNotebook, box, checkMutateFromModification, checkMutateToDef, codeBox, codeSpan, continueRangePosition, delay, envFor, evalOutput, exprBox, findDefs, getBox, getRangePosition, getRanges, grp, initNotebook, makeRange, markupDefs, nodeEnd, prepExpr, removeOldDefs, root, selInDef, textNode;
+  var Leisure, ReplCore, addsLine, bindNotebook, box, checkMutateFromModification, checkMutateToDef, codeBox, codeSpan, continueRangePosition, delay, envFor, evalOutput, findDefs, getBox, getRangePosition, getRanges, grp, initNotebook, makeOutputBox, makeRange, markupDefs, nodeEnd, prepExpr, removeOldDefs, root, selInDef, textNode, toDefBox, toExprBox;
 
   if ((typeof window !== "undefined" && window !== null) && (!(typeof global !== "undefined" && global !== null) || global === window)) {
     window.global = window;
@@ -57,6 +57,7 @@
             sp.setAttribute('generatedNL', '');
             bx = box(s.getRangeAt(0), 'codeMainExpr', true);
             bx.appendChild(sp);
+            makeOutputBox(bx);
             r = document.createRange();
             r.setStart(sp, 0);
             s.removeAllRanges();
@@ -79,15 +80,25 @@
     if (b != null) {
       inDef = selInDef();
       if (inDef && b.classList.contains('codeMainExpr')) {
-        b.classList.remove('codeMainExpr');
-        return b.classList.add('codeMain');
+        return toDefBox(b);
       } else if (!inDef && b.classList.contains('codeMain')) {
-        b.classList.remove('codeMain');
-        return b.classList.add('codeMainExpr');
+        return toExprBox(b);
       }
     }
   };
 
+  toExprBox = function toExprBox(b) {
+    b.classList.remove('codeMain');
+    b.classList.add('codeMainExpr');
+    return makeOutputBox(b);
+  };
+
+  toDefBox = function toDefBox(b) {
+    if (b.output) b.parentNode.removeChild(b.output);
+    b.classList.remove('codeMainExpr');
+    return b.classList.add('codeMain');
+  };
+
   selInDef = function selInDef(expectedClass) {
     var box, defType, leading, m, matched, name, r, s, txt;
     s = window.getSelection();
@@ -109,10 +120,7 @@
     if (!el.replacing) {
       s = window.getSelection();
       r = s.getRangeAt(0);
-      if (p = selInDef('codeMainExpr')) {
-        p.classList.remove('codeMainExpr');
-        return p.classList.add('codeMain');
-      }
+      if (p = selInDef('codeMainExpr')) return toDefBox(p);
     }
   };
 
@@ -193,7 +201,7 @@
         s.setAttribute('generatedNL', '');
         bx = box(main, 'codeMainExpr', true);
         bx.appendChild(s);
-        bx.parentNode.insertBefore(exprBox(bx), bx.nextSibling);
+        makeOutputBox(bx);
       }
     }
     return pgm;
@@ -227,7 +235,7 @@
     };
   };
 
-  exprBox = function exprBox(source) {
+  makeOutputBox = function makeOutputBox(source) {
     var node;
     node = document.createElement('div');
     node.setAttribute('LeisureOutput', '');
@@ -235,8 +243,10 @@
     node.setAttribute('class', 'output');
     node.setAttribute('contentEditable', 'false');
     node.source = source;
+    source.output = node;
     node.innerHTML = "<button onclick='Notebook.evalOutput(this.parentNode)'>-&gt;</button>";
     node.appendChild(textNode(' \n'));
+    source.parentNode.insertBefore(node, source.nextSibling);
     return node;
   };