diff --git a/Lexer.js b/Lexer.js
index dadaa68ad..c4cc02608 100644
--- a/Lexer.js
+++ b/Lexer.js
@@ -62,7 +62,7 @@ Lexer.prototype.lex = function(pos) {
     }
 
     // We didn't match any of the tokens, so throw an error.
-    throw "Unexpected character: '" + input[0] + "' at position " + this._pos;
+    throw "Unexpected character: '" + input[0] + "' at position " + pos;
 };
 
 module.exports = Lexer;
diff --git a/Parser.js b/Parser.js
index 71b84eedb..a971f8ea2 100644
--- a/Parser.js
+++ b/Parser.js
@@ -337,7 +337,7 @@ Parser.prototype.parseNucleus = function(pos) {
         var group = this.parseGroup(nucleus.position);
         if (group) {
             return new ParseResult(
-                new ParseNode(nucleus.type.slice(1), nucleus.text),
+                new ParseNode(nucleus.type.slice(1), group.result),
                 group.position);
         } else {
             throw "Parse error: Expected group after '" + nucleus.text + "'";
diff --git a/katex.js b/katex.js
index 9413e9c90..48f54c2fc 100644
--- a/katex.js
+++ b/katex.js
@@ -129,10 +129,10 @@ var buildGroup = function(style, color, group, prev) {
             return makeSpan("mord mspace " + spacingClassMap[group.value]);
         }
     } else if (group.type === "llap") {
-        var inner = makeSpan("", buildExpression(style, color, group.value));
+        var inner = makeSpan("", [buildGroup(style, color, group.value)]);
         return makeSpan("llap " + style.cls(), [inner]);
     } else if (group.type === "rlap") {
-        var inner = makeSpan("", buildExpression(style, color, group.value));
+        var inner = makeSpan("", [buildGroup(style, color, group.value)]);
         return makeSpan("rlap " + style.cls(), [inner]);
     } else if (group.type === "punct") {
         return makeSpan("mpunct" + color, [textit(group.value)]);