Allow reserved words to be used without slowing down most operations in browsers with faster foo.bar vs. foo['bar'].

lib/handlebars/vm.js

@@ -1,8 +1,6 @@
 var Handlebars = {};
 Handlebars.parse = require("handlebars/compiler").Handlebars.parse;
 
-if(typeof puts === "undefined") { var puts = function() {}; };
-
 // BEGIN(BROWSER)
 Handlebars.Compiler = function() {};
 Handlebars.JavaScriptCompiler = function() {};
@@ -252,8 +250,8 @@ Handlebars.JavaScriptCompiler = function() {};
 
       this.compileChildren(environment);
 
-      puts(environment.disassemble());
-      puts("")
+      //puts(environment.disassemble());
+      //puts("")
 
       var opcodes = environment.opcodes;
       var opcode, name;
@@ -317,8 +315,8 @@ Handlebars.JavaScriptCompiler = function() {};
       var fn = Function.apply(this, params);
       fn.displayName = "Handlebars.js"
 
-      puts(fn.toString())
-      puts("")
+      //puts(fn.toString())
+      //puts("")
 
       container.render = fn;
 
@@ -355,11 +353,19 @@ Handlebars.JavaScriptCompiler = function() {};
       }
     },
 
+    nameLookup: function(parent, name) {
+      if(JavaScriptCompiler.RESERVED_WORDS[name]) {
+        return parent + "['" + name + "']";
+      } else {
+        return parent + "." + name;
+      }
+    },
+
     lookupWithFallback: function(name) {
       if(name) {
-        this.pushStack("currentContext." + name);
+        this.pushStack(this.nameLookup('currentContext', name));
         var topStack = this.topStack();
-        this.source.push("if(" + topStack + " == null) { " + topStack + " = helpers." + name + "; }");
+        this.source.push("if(" + topStack + " == null) { " + topStack + " = " + this.nameLookup('helpers', name) + "; }");
       } else {
         this.pushStack("currentContext");
       }
@@ -367,7 +373,7 @@ Handlebars.JavaScriptCompiler = function() {};
 
     lookup: function(name) {
       var topStack = this.topStack();
-      this.source.push(topStack + " = " + topStack + "." + name + ";");
+      this.source.push(topStack + " = " + this.nameLookup(topStack, name) + ";");
     },
 
     pushString: function(string) {
@@ -482,7 +488,7 @@ Handlebars.JavaScriptCompiler = function() {};
     },
 
     invokePartial: function(context) {
-      this.pushStack("Handlebars.VM.invokePartial(partials." + context + ", '" + context + "', " + this.popStack() + ", helpers, partials);");
+      this.pushStack("Handlebars.VM.invokePartial(" + this.nameLookup('partials', context) + ", '" + context + "', " + this.popStack() + ", helpers, partials);");
     },
 
     escape: function() {
@@ -535,6 +541,16 @@ Handlebars.JavaScriptCompiler = function() {};
     }
   }
 
+  var reservedWords = ("break case catch continue default delete do else finally " +
+                       "for function if in instanceof new return switch this throw " + 
+                       "try typeof var void while with null true false").split(" ");
+
+  compilerWords = JavaScriptCompiler.RESERVED_WORDS = {};
+
+  for(var i=0, l=reservedWords.length; i<l; i++) {
+    compilerWords[reservedWords[i]] = true;
+  }
+
 })(Handlebars.Compiler, Handlebars.JavaScriptCompiler)
 
 Handlebars.VM = {