--- loncom/html/adm/LC_math_editor/src/enode.js	2014/09/24 18:14:39	1.1
+++ loncom/html/adm/LC_math_editor/src/enode.js	2015/02/24 15:20:44	1.2
@@ -18,19 +18,26 @@ through which recipients can access the
 
 */
 
+"use strict";
+
 /**
- * Parsed tree node. ENode.toMathML(hcolors) contains the code for the transformation into MathML.
+ * Parsed tree node. ENode.toMathML() contains the code for the transformation into MathML.
  * @constructor
- * @param {number} type - ENode.UNKNOWN | NAME | NUMBER | OPERATOR | FUNCTION | VECTOR
+ * @param {number} type - ENode.UNKNOWN | NAME | NUMBER | OPERATOR | FUNCTION | VECTOR | INTERVAL | SET | SUBSCRIPT
  * @param {Operator} op - The operator
  * @param {string} value - Node value as a string, null for type VECTOR
- * @param {Array.<ENode>} children - The children nodes, only for types OPERATOR, FUNCTION, VECTOR, SUBSCRIPT
+ * @param {Array.<ENode>} children - The children nodes, only for types OPERATOR, FUNCTION, VECTOR, INTERVAL, SET, SUBSCRIPT
+ * @param {number} [interval_type] - ENode.NOT_AN_INTERVAL | OPEN_OPEN | OPEN_CLOSED | CLOSED_OPEN | CLOSED_CLOSED
  */
-function ENode(type, op, value, children) {
+function ENode(type, op, value, children, interval_type) {
     this.type = type;
     this.op = op;
     this.value = value;
     this.children = children;
+    if (typeof interval_type == "undefined")
+        this.interval_type = ENode.NOT_AN_INTERVAL;
+    else
+        this.interval_type = interval_type;
 }
 
 ENode.UNKNOWN = 0;
@@ -39,11 +46,19 @@ ENode.NUMBER = 2;
 ENode.OPERATOR = 3;
 ENode.FUNCTION = 4;
 ENode.VECTOR = 5;
-ENode.SUBSCRIPT = 6;
+ENode.INTERVAL = 6;
+ENode.SET = 7;
+ENode.SUBSCRIPT = 8;
 ENode.COLORS = ["#E01010", "#0010FF", "#009000", "#FF00FF", "#00B0B0", "#F09000", 
                 "#800080", "#F080A0", "#6090F0", "#902000", "#70A050", "#A07060",
                 "#5000FF", "#E06050", "#008080", "#808000"];
 
+ENode.NOT_AN_INTERVAL = 0;
+ENode.OPEN_OPEN = 1;
+ENode.OPEN_CLOSED = 2;
+ENode.CLOSED_OPEN = 3;
+ENode.CLOSED_CLOSED = 4;
+
 /**
  * Returns the node as a string, for debug
  * @returns {string}
@@ -69,6 +84,12 @@ ENode.prototype.toString = function() {
         case ENode.VECTOR:
             s += 'VECTOR';
             break;
+        case ENode.INTERVAL:
+            s += 'INTERVAL';
+            break;
+        case ENode.SET:
+            s += 'SET';
+            break;
         case ENode.SUBSCRIPT:
             s += 'SUBSCRIPT';
             break;
@@ -86,6 +107,9 @@ ENode.prototype.toString = function() {
         }
         s += ']';
     }
+    if (this.interval_type) {
+        s += " " + this.interval_type;
+    }
     s+= ')';
     return s;
 };
@@ -96,26 +120,40 @@ ENode.prototype.toString = function() {
  * @param {Object.<string, string>} hcolors - hash identifier->color
  * @returns {string}
  */
-ENode.prototype.getColorForIdentifier = function(name, hcolors) {
-    var res = hcolors[name];
+ENode.prototype.getColorForIdentifier = function(name, context) {
+    var res = context.hcolors[name];
     if (!res) {
-        res = ENode.COLORS[Object.keys(hcolors).length % ENode.COLORS.length];
-        hcolors[name] = res;
+        var colors;
+        if (context.colors)
+            colors = context.colors;
+        else
+            colors = ENode.COLORS;
+        res = colors[Object.keys(context.hcolors).length % colors.length];
+        context.hcolors[name] = res;
     }
     return res;
 }
 
 /**
  * Transforms this ENode into a MathML HTML DOM element.
- * @param {Object} [context] - display context (not needed for the root element)
+ * @param {Array.<string>} [colors] - optional override for ENode.COLORS
+ * @returns {Element}
+ */
+ENode.prototype.toMathML = function(colors) {
+    var context = { hcolors: {}, depth: 0 , colors: colors};
+    return(this._toMathML(context));
+}
+
+/**
+ * Transforms this ENode into a MathML HTML DOM element (internal function).
+ * @param {Object} context - display context
  * @param {Object.<string, string>} context.hcolors - hash identifier->color
  * @param {number} context.depth - Depth in parenthesis, used for coloring
+ * @param {Array.<string>} context.colors - optional override for ENode.COLORS
  * @returns {Element}
  */
-ENode.prototype.toMathML = function(context) {
-    var c0, c1, c2, c3, c4, i, j, el, par, mrow, mo, mtable, mfrac, msub, msup;
-    if (typeof context == "undefined")
-        context = { hcolors: {}, depth: 0 };
+ENode.prototype._toMathML = function(context) {
+    var c0, c1, c2, c3, c4, i, j, el, par, mrow, mo, mtable, mfrac, msub, msup, mrow2;
     if (this.children != null && this.children.length > 0)
         c0 = this.children[0];
     else
@@ -153,7 +191,9 @@ ENode.prototype.toMathML = function(cont
             } else {
                 el = this.mi(this.value)
             }
-            el.setAttribute("mathcolor", this.getColorForIdentifier(this.value, context.hcolors));
+            el.setAttribute("mathcolor", this.getColorForIdentifier(this.value, context));
+            if (this.value.indexOf('$') === 0)
+                el.setAttribute("fontfamily", "monospace");
             return(el);
         
         case ENode.NUMBER:
@@ -175,8 +215,8 @@ ENode.prototype.toMathML = function(cont
         case ENode.OPERATOR:
             if (this.value == "/") {
                 mfrac = document.createElement('mfrac');
-                mfrac.appendChild(c0.toMathML(context));
-                mfrac.appendChild(c1.toMathML(context));
+                mfrac.appendChild(c0._toMathML(context));
+                mfrac.appendChild(c1._toMathML(context));
                 el = mfrac;
             } else if (this.value == "^") {
                 if (c0.type == ENode.FUNCTION) {
@@ -193,14 +233,14 @@ ENode.prototype.toMathML = function(cont
                 if (par)
                     el.appendChild(this.addP(c0, context));
                 else
-                    el.appendChild(c0.toMathML(context));
-                el.appendChild(c1.toMathML(context));
+                    el.appendChild(c0._toMathML(context));
+                el.appendChild(c1._toMathML(context));
             } else if (this.value == "*") {
                 mrow = document.createElement('mrow');
                 if (c0.type == ENode.OPERATOR && (c0.value == "+" || c0.value == "-"))
                     mrow.appendChild(this.addP(c0, context));
                 else
-                    mrow.appendChild(c0.toMathML(context));
+                    mrow.appendChild(c0._toMathML(context));
                 // should the x operator be visible ? We need to check if there is a number to the left of c1
                 var firstinc1 = c1;
                 while (firstinc1.type == ENode.OPERATOR) {
@@ -213,23 +253,27 @@ ENode.prototype.toMathML = function(cont
                     mrow.appendChild(this.mo("*"));
                 else if (firstinc1.type == ENode.NUMBER)
                     mrow.appendChild(this.mo("\u22C5"));
+                else if (context.units)
+                    mrow.appendChild(this.mo("\u22C5"));
+                else
+                    mrow.appendChild(this.mo("\u2062")); // invisible multiplication
                 if (c1.type == ENode.OPERATOR && (c1.value == "+" || c1.value == "-"))
                     mrow.appendChild(this.addP(c1, context));
                 else
-                    mrow.appendChild(c1.toMathML(context));
+                    mrow.appendChild(c1._toMathML(context));
                 el = mrow;
             } else if (this.value == "-") {
                 mrow = document.createElement('mrow');
                 if (this.children.length == 1) {
                     mrow.appendChild(this.mo("-"));
-                    mrow.appendChild(c0.toMathML(context));
+                    mrow.appendChild(c0._toMathML(context));
                 } else {
-                    mrow.appendChild(c0.toMathML(context));
+                    mrow.appendChild(c0._toMathML(context));
                     mrow.appendChild(this.mo("-"));
                     if (c1.type == ENode.OPERATOR && (c1.value == "+" || c1.value == "-"))
                         mrow.appendChild(this.addP(c1, context));
                     else
-                        mrow.appendChild(c1.toMathML(context));
+                        mrow.appendChild(c1._toMathML(context));
                 }
                 el = mrow;
             } else if (this.value == "!") {
@@ -238,13 +282,13 @@ ENode.prototype.toMathML = function(cont
                 if (c0.type == ENode.OPERATOR && (c0.value == "+" || c0.value == "-"))
                     mrow.appendChild(this.addP(c0, context));
                 else
-                    mrow.appendChild(c0.toMathML(context));
+                    mrow.appendChild(c0._toMathML(context));
                 mrow.appendChild(mo);
                 el = mrow;
             } else if (this.value == "+") {
                 mrow = document.createElement('mrow');
                 mo = this.mo(this.value);
-                mrow.appendChild(c0.toMathML(context));
+                mrow.appendChild(c0._toMathML(context));
                 mrow.appendChild(mo);
                 // should we add parenthesis ? We need to check if there is a '-' to the left of c1
                 par = false;
@@ -262,42 +306,50 @@ ENode.prototype.toMathML = function(cont
                 if (par)
                     mrow.appendChild(this.addP(c1, context));
                 else
-                    mrow.appendChild(c1.toMathML(context));
+                    mrow.appendChild(c1._toMathML(context));
                 el = mrow;
             } else if (this.value == ".") {
                 mrow = document.createElement('mrow');
                 if (c0.type == ENode.OPERATOR && (c0.value == "+" || c0.value == "-"))
                     mrow.appendChild(this.addP(c0, context));
                 else
-                    mrow.appendChild(c0.toMathML(context));
+                    mrow.appendChild(c0._toMathML(context));
                 mrow.appendChild(this.mo("\u22C5"));
                 if (c1.type == ENode.OPERATOR && (c1.value == "+" || c1.value == "-"))
                     mrow.appendChild(this.addP(c1, context));
                 else
-                    mrow.appendChild(c1.toMathML(context));
+                    mrow.appendChild(c1._toMathML(context));
                 el = mrow;
             } else if (this.value == "`") {
                 mrow = document.createElement('mrow');
                 if (c0.type == ENode.OPERATOR && (c0.value == "+" || c0.value == "-"))
                     mrow.appendChild(this.addP(c0, context));
                 else
-                    mrow.appendChild(c0.toMathML(context));
+                    mrow.appendChild(c0._toMathML(context));
                 // the units should not be in italics
+                // unit multiplication should not be displayed with an invisible operator
                 var mstyle = document.createElement("mstyle");
                 mstyle.setAttribute("fontstyle", "normal");
+                var units_context = {};
+                for (var prop in context) {
+                    if (context.hasOwnProperty(prop)) {
+                        units_context[prop] = context[prop];
+                    }
+                }
+                units_context.units = true;
                 if (c1.type == ENode.OPERATOR && (c1.value == "+" || c1.value == "-"))
-                    mstyle.appendChild(this.addP(c1, context));
+                    mstyle.appendChild(this.addP(c1, units_context));
                 else
-                    mstyle.appendChild(c1.toMathML(context));
+                    mstyle.appendChild(c1._toMathML(units_context));
                 mrow.appendChild(mstyle);
                 el = mrow;
             } else {
                 // relational operators
                 mrow = document.createElement('mrow');
                 mo = this.mo(this.value);
-                mrow.appendChild(c0.toMathML(context));
+                mrow.appendChild(c0._toMathML(context));
                 mrow.appendChild(mo);
-                mrow.appendChild(c1.toMathML(context));
+                mrow.appendChild(c1._toMathML(context));
                 el = mrow;
             }
             return(el);
@@ -306,24 +358,24 @@ ENode.prototype.toMathML = function(cont
             // c0 contains the function name
             if (c0.value == "sqrt" && c1 != null) {
                 el = document.createElement('msqrt');
-                el.appendChild(c1.toMathML(context));
+                el.appendChild(c1._toMathML(context));
             } else if (c0.value == "abs" && c1 != null) {
                 mrow = document.createElement('mrow');
                 mrow.appendChild(this.mo("|"));
-                mrow.appendChild(c1.toMathML(context));
+                mrow.appendChild(c1._toMathML(context));
                 mrow.appendChild(this.mo("|"));
                 el = mrow;
             } else if (c0.value == "exp" && c1 != null) {
                 el = document.createElement('msup');
                 el.appendChild(this.mi("e"));
-                el.appendChild(c1.toMathML(context));
+                el.appendChild(c1._toMathML(context));
             } else if (c0.value == "factorial") {
                 mrow = document.createElement('mrow');
                 mo = this.mo("!");
                 if (c1.type == ENode.OPERATOR && (c1.value == "+" || c1.value == "-"))
                     mrow.appendChild(this.addP(c1, context));
                 else
-                    mrow.appendChild(c1.toMathML(context));
+                    mrow.appendChild(c1._toMathML(context));
                 mrow.appendChild(mo);
                 el = mrow;
             } else if (c0.value == "diff" && this.children != null && this.children.length == 3) {
@@ -338,27 +390,27 @@ ENode.prototype.toMathML = function(cont
                 if (c1.type == ENode.OPERATOR && (c1.value == "+" || c1.value == "-"))
                     mrow.appendChild(this.addP(c1, context));
                 else
-                    mrow.appendChild(c1.toMathML(context));
+                    mrow.appendChild(c1._toMathML(context));
                 el = mrow;
             } else if (c0.value == "diff" && this.children != null && this.children.length == 4) {
                 mrow = document.createElement('mrow');
                 mfrac = document.createElement('mfrac');
                 msup = document.createElement('msup');
                 msup.appendChild(this.mi("d"));
-                msup.appendChild(c3.toMathML(context));
+                msup.appendChild(c3._toMathML(context));
                 mfrac.appendChild(msup);
                 var f2 = document.createElement('mrow');
                 f2.appendChild(this.mi("d"));
                 msup = document.createElement('msup');
-                msup.appendChild(c2.toMathML(context));
-                msup.appendChild(c3.toMathML(context));
+                msup.appendChild(c2._toMathML(context));
+                msup.appendChild(c3._toMathML(context));
                 f2.appendChild(msup);
                 mfrac.appendChild(f2);
                 mrow.appendChild(mfrac);
                 if (c1.type == ENode.OPERATOR && (c1.value == "+" || c1.value == "-"))
                     mrow.appendChild(this.addP(c1, context));
                 else
-                    mrow.appendChild(c1.toMathML(context));
+                    mrow.appendChild(c1._toMathML(context));
                 el = mrow;
             } else if (c0.value == "integrate" && this.children != null && this.children.length == 3) {
                 mrow = document.createElement('mrow');
@@ -368,9 +420,9 @@ ENode.prototype.toMathML = function(cont
                 if (c2.type == ENode.OPERATOR && (c2.value == "+" || c2.value == "-"))
                     mrow.appendChild(this.addP(c1, context));
                 else
-                    mrow.appendChild(c1.toMathML(context));
+                    mrow.appendChild(c1._toMathML(context));
                 mrow.appendChild(this.mi("d"));
-                mrow.appendChild(c2.toMathML(context));
+                mrow.appendChild(c2._toMathML(context));
                 el = mrow;
             } else if (c0.value == "integrate" && this.children != null && this.children.length == 5) {
                 mrow = document.createElement('mrow');
@@ -378,15 +430,15 @@ ENode.prototype.toMathML = function(cont
                 var mo = this.mo("\u222B");
                 mo.setAttribute("stretchy", "true"); // doesn't work with MathJax
                 msubsup.appendChild(mo);
-                msubsup.appendChild(c3.toMathML(context));
-                msubsup.appendChild(c4.toMathML(context));
+                msubsup.appendChild(c3._toMathML(context));
+                msubsup.appendChild(c4._toMathML(context));
                 mrow.appendChild(msubsup);
                 if (c2.type == ENode.OPERATOR && (c2.value == "+" || c2.value == "-"))
                     mrow.appendChild(this.addP(c1, context));
                 else
-                    mrow.appendChild(c1.toMathML(context));
+                    mrow.appendChild(c1._toMathML(context));
                 mrow.appendChild(this.mi("d"));
-                mrow.appendChild(c2.toMathML(context));
+                mrow.appendChild(c2._toMathML(context));
                 el = mrow;
             } else if (c0.value == "sum" && this.children != null && this.children.length == 5) {
                 mrow = document.createElement('mrow');
@@ -394,17 +446,17 @@ ENode.prototype.toMathML = function(cont
                 var mo = this.mo("\u2211");
                 mo.setAttribute("stretchy", "true"); // doesn't work with MathJax
                 munderover.appendChild(mo);
-                var mrow2 = document.createElement('mrow');
-                mrow2.appendChild(c2.toMathML(context));
+                mrow2 = document.createElement('mrow');
+                mrow2.appendChild(c2._toMathML(context));
                 mrow2.appendChild(this.mo("="));
-                mrow2.appendChild(c3.toMathML(context));
+                mrow2.appendChild(c3._toMathML(context));
                 munderover.appendChild(mrow2);
-                munderover.appendChild(c4.toMathML(context));
+                munderover.appendChild(c4._toMathML(context));
                 mrow.appendChild(munderover);
                 if (c2.type == ENode.OPERATOR && (c2.value == "+" || c2.value == "-"))
                     mrow.appendChild(this.addP(c1, context));
                 else
-                    mrow.appendChild(c1.toMathML(context));
+                    mrow.appendChild(c1._toMathML(context));
                 el = mrow;
             } else if (c0.value == "product" && this.children != null && this.children.length == 5) {
                 mrow = document.createElement('mrow');
@@ -412,17 +464,17 @@ ENode.prototype.toMathML = function(cont
                 var mo = this.mo("\u220F");
                 mo.setAttribute("stretchy", "true"); // doesn't work with MathJax
                 munderover.appendChild(mo);
-                var mrow2 = document.createElement('mrow');
-                mrow2.appendChild(c2.toMathML(context));
+                mrow2 = document.createElement('mrow');
+                mrow2.appendChild(c2._toMathML(context));
                 mrow2.appendChild(this.mo("="));
-                mrow2.appendChild(c3.toMathML(context));
+                mrow2.appendChild(c3._toMathML(context));
                 munderover.appendChild(mrow2);
-                munderover.appendChild(c4.toMathML(context));
+                munderover.appendChild(c4._toMathML(context));
                 mrow.appendChild(munderover);
                 if (c2.type == ENode.OPERATOR && (c2.value == "+" || c2.value == "-"))
                     mrow.appendChild(this.addP(c1, context));
                 else
-                    mrow.appendChild(c1.toMathML(context));
+                    mrow.appendChild(c1._toMathML(context));
                 el = mrow;
             } else if (c0.value == "limit") {
                 mrow = document.createElement('mrow');
@@ -432,9 +484,9 @@ ENode.prototype.toMathML = function(cont
                     var munder = document.createElement('munder');
                     munder.appendChild(this.mo("lim"));
                     var mrowunder = document.createElement('mrow');
-                    mrowunder.appendChild(c2.toMathML(context));
+                    mrowunder.appendChild(c2._toMathML(context));
                     mrowunder.appendChild(this.mo("\u2192"));
-                    mrowunder.appendChild(c3.toMathML(context));
+                    mrowunder.appendChild(c3._toMathML(context));
                     if (c4 != null) {
                         if (c4.value == "plus")
                             mrowunder.appendChild(this.mo("+"));
@@ -444,7 +496,7 @@ ENode.prototype.toMathML = function(cont
                     munder.appendChild(mrowunder);
                     mrow.appendChild(munder);
                 }
-                mrow.appendChild(c1.toMathML(context));
+                mrow.appendChild(c1._toMathML(context));
                 el = mrow;
             } else if (c0.value == "binomial") {
                 // displayed like a vector
@@ -453,7 +505,7 @@ ENode.prototype.toMathML = function(cont
                 mtable = document.createElement('mtable');
                 for (i=1; i<this.children.length; i++) {
                     var mtr = document.createElement('mtr');
-                    mtr.appendChild(this.children[i].toMathML(context));
+                    mtr.appendChild(this.children[i]._toMathML(context));
                     mtable.appendChild(mtr);
                 }
                 mrow.appendChild(mtable);
@@ -474,20 +526,48 @@ ENode.prototype.toMathML = function(cont
                 for (i=1; i<this.children.length; i++) {
                     var mtr = document.createElement('mtr');
                     for (j=0; j<this.children[i].children.length; j++) {
-                        mtr.appendChild(this.children[i].children[j].toMathML(context));
+                        mtr.appendChild(this.children[i].children[j]._toMathML(context));
                     }
                     mtable.appendChild(mtr);
                 }
                 mrow.appendChild(mtable);
                 mrow.appendChild(this.mo(")"));
                 el = mrow;
+            } else if (c0.value == "union" && this.children.length == 3) {
+                for (i=1; i<this.children.length; i++) {
+                    // check that all children are intervals or sets
+                    if (this.children[i].type !== ENode.INTERVAL && this.children[i].type !== ENode.SET) {
+                        el = document.createElement('mtext');
+                        el.appendChild(document.createTextNode("???"));
+                        return(el);
+                    }
+                }
+                mrow = document.createElement('mrow');
+                mrow.appendChild(c1._toMathML(context));
+                mrow.appendChild(this.mo("\u222A"));
+                mrow.appendChild(c2._toMathML(context));
+                el = mrow;
+            } else if (c0.value == "intersection" && this.children.length == 3) {
+                for (i=1; i<this.children.length; i++) {
+                    // check that all children are intervals or sets
+                    if (this.children[i].type !== ENode.INTERVAL && this.children[i].type !== ENode.SET) {
+                        el = document.createElement('mtext');
+                        el.appendChild(document.createTextNode("???"));
+                        return(el);
+                    }
+                }
+                mrow = document.createElement('mrow');
+                mrow.appendChild(c1._toMathML(context));
+                mrow.appendChild(this.mo("\u2229"));
+                mrow.appendChild(c2._toMathML(context));
+                el = mrow;
             } else {
                 // default display for a function
                 mrow = document.createElement('mrow');
-                mrow.appendChild(c0.toMathML(context));
+                mrow.appendChild(c0._toMathML(context));
                 mrow.appendChild(this.mo("("));
                 for (i=1; i<this.children.length; i++) {
-                    mrow.appendChild(this.children[i].toMathML(context));
+                    mrow.appendChild(this.children[i]._toMathML(context));
                     if (i < this.children.length - 1)
                         mrow.appendChild(this.mo(Definitions.ARG_SEPARATOR));
                 }
@@ -509,32 +589,67 @@ ENode.prototype.toMathML = function(cont
                 var mtr = document.createElement('mtr');
                 if (is_matrix) {
                     for (j=0; j<this.children[i].children.length; j++) {
-                        mtr.appendChild(this.children[i].children[j].toMathML(context));
+                        mtr.appendChild(this.children[i].children[j]._toMathML(context));
                     }
                 } else {
-                    mtr.appendChild(this.children[i].toMathML(context));
+                    mtr.appendChild(this.children[i]._toMathML(context));
                 }
                 mtable.appendChild(mtr);
             }
             mrow.appendChild(mtable);
             mrow.appendChild(this.mo(")"));
             return(mrow);
+        
+        case ENode.INTERVAL:
+            mrow = document.createElement('mrow');
+            if (this.interval_type == ENode.OPEN_OPEN || this.interval_type == ENode.OPEN_CLOSED) {
+                mo = this.mo("(");
+            } else {
+                mo = this.mo("[");
+            }
+            mrow.appendChild(mo);
+            mrow2 = document.createElement('mrow');
+            mrow2.appendChild(this.children[0]._toMathML(context));
+            mrow2.appendChild(this.mo(":"));
+            mrow2.appendChild(this.children[1]._toMathML(context));
+            mrow.appendChild(mrow2);
+            if (this.interval_type == ENode.OPEN_OPEN || this.interval_type == ENode.CLOSED_OPEN) {
+                mo = this.mo(")");
+            } else {
+                mo = this.mo("]");
+            }
+            mrow.appendChild(mo);
+            return(mrow);
             
+        case ENode.SET:
+            mrow = document.createElement('mrow');
+            mrow.appendChild(this.mo("{"));
+            mrow2 = document.createElement('mrow');
+            for (i=0; i<this.children.length; i++) {
+                if (i > 0)
+                    mrow2.appendChild(this.mo(";"));
+                mrow2.appendChild(this.children[i]._toMathML(context));
+            }
+            mrow.appendChild(mrow2);
+            mrow.appendChild(this.mo("}"));
+            return(mrow);
+        
         case ENode.SUBSCRIPT:
             msub = document.createElement('msub');
-            msub.appendChild(c0.toMathML(context));
+            msub.appendChild(c0._toMathML(context));
             if (this.children.length > 2) {
                 mrow = document.createElement('mrow');
                 for (i=1; i<this.children.length; i++) {
-                    mrow.appendChild(this.children[i].toMathML(context));
+                    mrow.appendChild(this.children[i]._toMathML(context));
                     if (i < this.children.length - 1)
                         mrow.appendChild(this.mo(Definitions.ARG_SEPARATOR));
                 }
                 msub.appendChild(mrow);
             } else {
-                msub.appendChild(c1.toMathML(context));
+                msub.appendChild(c1._toMathML(context));
             }
             return(msub);
+            
     }
 };
 
@@ -587,13 +702,18 @@ ENode.prototype.addP = function(en, cont
     var mrow, mo;
     mrow = document.createElement('mrow');
     mo = this.mo("(");
-    mo.setAttribute("mathcolor", ENode.COLORS[context.depth % ENode.COLORS.length]);
+    var colors;
+    if (context.colors)
+        colors = context.colors;
+    else
+        colors = ENode.COLORS;
+    mo.setAttribute("mathcolor", colors[context.depth % colors.length]);
     mrow.appendChild(mo);
     context.depth++;
-    mrow.appendChild(en.toMathML(context));
+    mrow.appendChild(en._toMathML(context));
     context.depth--;
     mo = this.mo(")");
-    mo.setAttribute("mathcolor", ENode.COLORS[context.depth % ENode.COLORS.length]);
+    mo.setAttribute("mathcolor", colors[context.depth % colors.length]);
     mrow.appendChild(mo);
     return mrow;
 };