diff --git a/lib/compiler.js b/lib/compiler.js
index e1e1642..244755b 100644
--- a/lib/compiler.js
+++ b/lib/compiler.js
@@ -38,10 +38,12 @@ var compiler = {
    * during the generation and some may protrude to the generated parser and
    * cause its malfunction.
    */
-  compile: function(ast, passes) {
-    var options = arguments.length > 2 ? objects.clone(arguments[2]) : {},
-        stage;
+  compile: function(ast, passes, options) {
+    options = options !== void 0 ? options : {};
 
+    var stage;
+
+    options = objects.clone(options);
     objects.defaults(options, {
       allowedStartRules:  [ast.rules[0].name],
       cache:              false,
diff --git a/lib/compiler/passes/generate-js.js b/lib/compiler/passes/generate-js.js
index 62a5eca..799231e 100644
--- a/lib/compiler/passes/generate-js.js
+++ b/lib/compiler/passes/generate-js.js
@@ -437,13 +437,12 @@ function generateJS(ast, options) {
             return code;
           },
 
-          pop: function() {
-            var n, values;
+          pop: function(n) {
+            var values;
 
-            if (arguments.length === 0) {
+            if (n === void 0) {
               return s(this.sp--);
             } else {
-              n = arguments[0];
               values = arrays.map(arrays.range(this.sp - n + 1, this.sp + 1), s);
               this.sp -= n;
 
@@ -851,9 +850,10 @@ function generateJS(ast, options) {
   }
 
   parts.push([
-    '  function peg$parse(input) {',
-    '    var options = arguments.length > 1 ? arguments[1] : {},',
-    '        parser  = this,',
+    '  function peg$parse(input, options) {',
+    '    options = options !== void 0 ? options : {};',
+    '',
+    '    var parser = this,',
     '',
     '        peg$FAILED = {},',
     ''
diff --git a/lib/parser.js b/lib/parser.js
index 56c812a..dd38f53 100644
--- a/lib/parser.js
+++ b/lib/parser.js
@@ -28,9 +28,10 @@ module.exports = (function() {
 
   peg$subclass(peg$SyntaxError, Error);
 
-  function peg$parse(input) {
-    var options = arguments.length > 1 ? arguments[1] : {},
-        parser  = this,
+  function peg$parse(input, options) {
+    options = options !== void 0 ? options : {};
+
+    var parser = this,
 
         peg$FAILED = {},
 
diff --git a/lib/peg.js b/lib/peg.js
index 912cbe8..04475bb 100644
--- a/lib/peg.js
+++ b/lib/peg.js
@@ -22,7 +22,9 @@ var PEG = {
    * errors are detected during the generation and some may protrude to the
    * generated parser and cause its malfunction.
    */
-  buildParser: function(grammar) {
+  buildParser: function(grammar, options) {
+    options = options !== void 0 ? options : {};
+
     function convertPasses(passes) {
       var converted = {}, stage;
 
@@ -35,8 +37,9 @@ var PEG = {
       return converted;
     }
 
-    var options = arguments.length > 1 ? objects.clone(arguments[1]) : {},
-        plugins = "plugins" in options ? options.plugins : [],
+    options = objects.clone(options);
+
+    var plugins = "plugins" in options ? options.plugins : [],
         config  = {
           parser: this.parser,
           passes: convertPasses(this.compiler.passes)
diff --git a/spec/behavior/generated-parser-behavior.spec.js b/spec/behavior/generated-parser-behavior.spec.js
index 196491d..d45b1ed 100644
--- a/spec/behavior/generated-parser-behavior.spec.js
+++ b/spec/behavior/generated-parser-behavior.spec.js
@@ -34,14 +34,15 @@ describe("generated parser behavior", function() {
 
   beforeEach(function() {
     this.addMatchers({
-      toParse: function(input, expected) {
-        var options = arguments.length > 2 ? arguments[2] : {},
-            result;
+      toParse: function(input, expected, options) {
+        options = options !== undefined ? options : {};
+
+        var result;
 
         try {
           result = this.actual.parse(input, options);
 
-          if (arguments.length > 1) {
+          if (expected !== undefined) {
             this.message = function() {
               return "Expected " + jasmine.pp(input) + " "
                    + "with options " + jasmine.pp(options) + " "
@@ -58,7 +59,7 @@ describe("generated parser behavior", function() {
           this.message = function() {
             return "Expected " + jasmine.pp(input) + " "
                  + "with options " + jasmine.pp(options) + " "
-                 + "to parse" + (arguments.length > 1 ? " as " + jasmine.pp(expected) : "") + ", "
+                 + "to parse" + (expected !== undefined ? " as " + jasmine.pp(expected) : "") + ", "
                  + "but it failed to parse with message "
                  + jasmine.pp(e.message) + ".";
           };
@@ -67,9 +68,10 @@ describe("generated parser behavior", function() {
         }
       },
 
-      toFailToParse: function(input, details) {
-        var options = arguments.length > 2 ? arguments[2] : {},
-            result;
+      toFailToParse: function(input, details, options) {
+        options = options !== undefined ? options : {};
+
+        var result;
 
         try {
           result = this.actual.parse(input, options);
@@ -417,9 +419,14 @@ describe("generated parser behavior", function() {
     describe("positive semantic predicate", function() {
       describe("when the code returns a truthy value", function() {
         it("returns |undefined|", function() {
-          var parser = PEG.buildParser('start = &{ return true; }', options);
+          /*
+           * The |""| is needed so that the parser doesn't return just
+           * |undefined| which we can't compare against in |toParse| due to the
+           * way optional parameters work.
+           */
+          var parser = PEG.buildParser('start = &{ return true; } ""', options);
 
-          expect(parser).toParse("", undefined);
+          expect(parser).toParse("", [undefined, ""]);
         });
       });
 
@@ -617,9 +624,14 @@ describe("generated parser behavior", function() {
     describe("negative semantic predicate", function() {
       describe("when the code returns a falsey value", function() {
         it("returns |undefined|", function() {
-          var parser = PEG.buildParser('start = !{ return false; }', options);
+          /*
+           * The |""| is needed so that the parser doesn't return just
+           * |undefined| which we can't compare against in |toParse| due to the
+           * way optional parameters work.
+           */
+          var parser = PEG.buildParser('start = !{ return false; } ""', options);
 
-          expect(parser).toParse("", undefined);
+          expect(parser).toParse("", [undefined, ""]);
         });
       });
 
diff --git a/spec/unit/compiler/passes/helpers.js b/spec/unit/compiler/passes/helpers.js
index 5c862d5..504ca18 100644
--- a/spec/unit/compiler/passes/helpers.js
+++ b/spec/unit/compiler/passes/helpers.js
@@ -4,7 +4,9 @@
 
 beforeEach(function() {
   this.addMatchers({
-    toChangeAST: function(grammar, details) {
+    toChangeAST: function(grammar, details, options) {
+      options = options !== undefined ? options : {};
+
       function matchDetails(value, details) {
         function isArray(value) {
           return Object.prototype.toString.apply(value) === "[object Array]";
@@ -42,8 +44,7 @@ beforeEach(function() {
         }
       }
 
-      var options = arguments.length > 2 ? arguments[2] : {},
-          ast     = PEG.parser.parse(grammar);
+      var ast = PEG.parser.parse(grammar);
 
       this.actual(ast, options);