diff --git a/js/narcissus/jsexec.js b/js/narcissus/jsexec.js
index 531c28e86dd4..eb5184f93edc 100644
--- a/js/narcissus/jsexec.js
+++ b/js/narcissus/jsexec.js
@@ -307,7 +307,7 @@ Narcissus.interpreter = (function() {
                  : new TypeError(message);
     }
 
-    function valuatePhis(n, v) {
+    function evaluatePhis(n, v) {
         var ps = n.phiUses;
         if (!ps)
             return;
@@ -319,7 +319,7 @@ Narcissus.interpreter = (function() {
             if (ps[i].v === v)
                 break;
             ps[i].v = v;
-            valuatePhis(ps[i], v);
+            evaluatePhis(ps[i], v);
         }
     }
 
@@ -869,7 +869,7 @@ Narcissus.interpreter = (function() {
         if (n.backwards) {
             n.v = v;
         }
-        valuatePhis(n, v);
+        evaluatePhis(n, v);
 
         return v;
     }
diff --git a/js/narcissus/jsparse.js b/js/narcissus/jsparse.js
index 3983254c9c8c..0fa386b0140d 100644
--- a/js/narcissus/jsparse.js
+++ b/js/narcissus/jsparse.js
@@ -86,10 +86,8 @@ Narcissus.parser = (function() {
             if (typeof unbound !== "object")
                 continue;
 
-            /*
-             * We store the bound sub-builder as builder's own property
-             * so that we can have multiple builders at the same time.
-             */
+            // We store the bound sub-builder as builder's own property
+            // so that we can have multiple builders at the same time.
             var bound = builder[ns] = {};
             for (var m in unbound) {
                 bound[m] = bindMethod(unbound[m], builder);
diff --git a/js/narcissus/jsssa.js b/js/narcissus/jsssa.js
index 7680c0c17682..6e9bbd93602b 100644
--- a/js/narcissus/jsssa.js
+++ b/js/narcissus/jsssa.js
@@ -1068,21 +1068,18 @@
         for (var ns in super.prototype) {
             var childNS = childProto[ns];
             var superNS = superProto[ns];
-            var childNSType = typeof childNS;
-            if (childNSType === "undefined") {
+            if (childNS === undefined) {
                 childProto[ns] = superNS;
-            } else if (childNSType === "object") {
+            } else {
                 for (var m in superNS) {
                     let childMethod = childNS[m];
                     let superMethod = superNS[m];
-                    if (typeof childMethod === "undefined") {
+                    if (childMethod === undefined) {
                         childNS[m] = superMethod;
                     } else {
                         childNS[m] = function() {
-                            if (this.binds)
-                                return childMethod.apply(this, arguments);
-                            else
-                                return superMethod.apply(this, arguments);
+                            return (this.binds ? childMethod : superMethod)
+                                   .apply(this, arguments);
                         };
                     }
                 }