Various argument handling optimizations

Permits more aggressive v8 optimization.

lib/ClassBuilder.js

@@ -299,9 +299,10 @@ exports.prototype.build = function extend( _, __ )
     // ensure we'll be permitted to instantiate abstract classes for the base
     this._extending = true;
 
-    var args      = Array.prototype.slice.call( arguments ),
+    var a         = arguments,
-        props     = args.pop() || {},
+        an        = a.length,
-        base      = args.pop() || exports.ClassBase,
+        props     = ( ( an > 0 ) ? a[ an - 1 ] : 0 ) || {},
+        base      = ( ( an > 1 ) ? a[ an - 2 ] : 0 ) || exports.ClassBase,
         prototype = this._getBase( base ),
         cname     = '',
         autoa     = false,
@@ -508,7 +509,10 @@ exports.prototype.buildMembers = function buildMembers(
         {
             handlers[ name ] = function()
             {
-                var args = Array.prototype.slice.call( arguments );
+                var args = [],
+                    i    = arguments.length;
+
+                while ( i-- ) args[ i ] = arguments[ i ];
 
                 // invoke the custom handler with the original handler as
                 // its last argument (which the custom handler may choose

lib/class.js

@@ -64,19 +64,24 @@ var _nullf = function() { return null; }
 module.exports = function( namedef, def )
 {
     var type   = ( typeof namedef ),
-        result = null
+        result = null,
+        args   = [],
+        i      = arguments.length
     ;
 
+    // passing arguments object prohibits optimizations in v8
+    while ( i-- ) args[ i ] = arguments[ i ];
+
     switch ( type )
     {
         // anonymous class
         case 'object':
-            result = createAnonymousClass.apply( null, arguments );
+            result = createAnonymousClass.apply( null, args );
             break;
 
         // named class
         case 'string':
-            result = createNamedClass.apply( null, arguments );
+            result = createNamedClass.apply( null, args );
             break;
 
         default:
@@ -99,10 +104,7 @@ module.exports = function( namedef, def )
  *
  * @return  {Function}  extended class
  */
-module.exports.extend = function( baseordfn, dfn )
+module.exports.extend = extend;
-{
-    return extend.apply( this, arguments );
-};
 
 
 /**
@@ -138,11 +140,11 @@ module.exports.implement = function( interfaces )
  */
 module.exports.use = function( traits )
 {
+    var args = [], i = arguments.length;
+    while( i-- ) args[ i ] = arguments[ i ];
+
     // consume traits onto an empty base
-    return createUse(
+    return createUse( _nullf, args );
-        _nullf,
-        Array.prototype.slice.call( arguments )
-    );
 };
 
 
@@ -292,7 +294,10 @@ function createStaging( cname )
     return {
         extend: function()
         {
-            var args = Array.prototype.slice.apply( arguments );
+            var args = [],
+                i    = arguments.length;
+
+            while ( i-- ) args[ i ] = arguments[ i ];
 
             // extend() takes a maximum of two arguments. If only one
             // argument is provided, then it is to be the class definition.
@@ -308,21 +313,24 @@ function createStaging( cname )
 
         implement: function()
         {
+            var args = [],
+                i    = arguments.length;
+
+            while ( i-- ) args[ i ] = arguments[ i ];
+
             // implement on empty base, providing the class name to be used once
             // extended
-            return createImplement(
+            return createImplement( null, args, cname );
-                null,
-                Array.prototype.slice.call( arguments ),
-                cname
-            );
         },
 
         use: function()
         {
-            return createUse(
+            var args = [],
-                _nullf,
+                i    = arguments.length;
-                Array.prototype.slice.call( arguments )
+
-            );
+            while ( i-- ) args[ i ] = arguments[ i ];
+
+            return createUse( _nullf, args );
         },
     };
 }
@@ -349,14 +357,14 @@ function createImplement( base, ifaces, cname )
     var partial = {
         extend: function()
         {
-            var args     = Array.prototype.slice.call( arguments ),
+            var an       = arguments.length,
-                def      = args.pop(),
+                def      = arguments[ an - 1 ],
-                ext_base = args.pop()
+                ext_base = ( an > 1 ) ? arguments[ an - 2 ] : null
             ;
 
             // if any arguments remain, then they likely misunderstood what this
             // method does
-            if ( args.length > 0 )
+            if ( an > 2 )
             {
                 throw Error(
                     "Expecting no more than two arguments for extend()"
@@ -394,7 +402,12 @@ function createImplement( base, ifaces, cname )
         // much more performant (it creates a subtype before mixing in)
         use: function()
         {
-            var traits = Array.prototype.slice.call( arguments );
+            var traits = [],
+                i      = arguments.length;
+
+            // passing arguments object prohibits optimizations in v8
+            while ( i-- ) traits[ i ] = arguments[ i ];
+
             return createUse(
                 function() { return partial.__createBase(); },
                 traits
@@ -468,9 +481,9 @@ function createUse( basef, traits, nonbase )
     // given during the extend operation
     partial.extend = function()
     {
-        var args     = Array.prototype.slice.call( arguments ),
+        var an       = arguments.length,
-            dfn      = args.pop(),
+            dfn      = arguments[ an - 1 ],
-            ext_base = args.pop(),
+            ext_base = ( an > 1 ) ? arguments[ an - 2 ] : null,
             base     = basef();
 
         // extend the mixed class, which ensures that all super references
@@ -485,12 +498,17 @@ function createUse( basef, traits, nonbase )
     // call simply to mix in another trait
     partial.use = function()
     {
+        var args = [],
+            i    = arguments.length;
+
+        while ( i-- ) args[ i ] = arguments[ i ];
+
         return createUse(
             function()
             {
                 return partial.__createBase();
             },
-            Array.prototype.slice.call( arguments ),
+            args,
             nonbase
         );
     };
@@ -557,8 +575,14 @@ function createMixedClass( base, traits )
  */
 function extend( _, __ )
 {
+    var args = [],
+        i    = arguments.length;
+
+    // passing arguments object prohibits optimizations in v8
+    while ( i-- ) args[ i ] = arguments[ i ];
+
     // set up the new class
-    var new_class = class_builder.build.apply( class_builder, arguments );
+    var new_class = class_builder.build.apply( class_builder, args );
 
     // set up some additional convenience props
     setupProps( new_class );
@@ -584,10 +608,9 @@ function extend( _, __ )
  */
 var implement = function( baseobj, interfaces )
 {
-    var args = Array.prototype.slice.call( arguments ),
+    var an   = arguments.length,
         dest = {},
-        base = args.pop(),
+        base = arguments[ an - 1 ],
-        len  = args.length,
         arg  = null,
 
         implemented   = [],
@@ -595,9 +618,9 @@ var implement = function( baseobj, interfaces )
     ;
 
     // add each of the interfaces
-    for ( var i = 0; i < len; i++ )
+    for ( var i = 0; i < ( an - 1 ); i++ )
     {
-        arg = args[ i ];
+        arg = arguments[ i ];
 
         // copy all interface methods to the class (does not yet deep copy)
         util.propParse( arg.prototype, {
@@ -678,10 +701,10 @@ function attachImplement( func )
 {
     util.defineSecureProp( func, 'implement', function()
     {
-        return createImplement(
+        var args = [], i = arguments.length;
-            func,
+        while( i-- ) args[ i ] = arguments[ i ];
-            Array.prototype.slice.call( arguments )
+
-        );
+        return createImplement( func, args );
     });
 }
 
@@ -699,11 +722,10 @@ function attachUse( func )
 {
     util.defineSecureProp( func, 'use', function()
     {
-        return createUse(
+        var args = [], i = arguments.length;
-            function() { return func; },
+        while( i-- ) args[ i ] = arguments[ i ];
-            Array.prototype.slice.call( arguments ),
+
-            true
+        return createUse( function() { return func; }, args, true );
-        );
     } );
 }
 

lib/class_abstract.js

@@ -33,7 +33,7 @@ var Class = require( __dirname + '/class' );
  */
 module.exports = exports = function()
 {
-    markAbstract( arguments );
+    markAbstract( arguments[ arguments.length - 1 ] );
 
     // forward everything to Class
     var result = Class.apply( this, arguments );
@@ -56,7 +56,7 @@ module.exports = exports = function()
  */
 exports.extend = function()
 {
-    markAbstract( arguments );
+    markAbstract( arguments[ arguments.length - 1 ] );
     return Class.extend.apply( this, arguments );
 };
 
@@ -92,18 +92,12 @@ exports.implement = function()
 /**
  * Causes a definition to be flagged as abstract
  *
- * This function assumes the last argument to be the definition, which is the
+ * @param  {*}  dfn  suspected definition object
- * common case, and modifies the object referenced by that argument.
- *
- * @param  {Arguments}  args  arguments to parse
  *
  * @return  {undefined}
  */
-function markAbstract( args )
+function markAbstract( dfn )
 {
-    // the last argument _should_ be the definition
-    var dfn = args[ args.length - 1 ];
-
     if ( typeof dfn === 'object' )
     {
         // mark as abstract
@@ -141,7 +135,7 @@ function abstractOverride( obj )
     // wrap extend, applying the abstract flag
     obj.extend = function()
     {
-        markAbstract( arguments );
+        markAbstract( arguments[ arguments.length - 1 ] );
         return extend.apply( this, arguments );
     };
 

lib/class_final.js

@@ -29,7 +29,7 @@ var Class = require( __dirname + '/class' );
  */
 exports = module.exports = function()
 {
-    markFinal( arguments );
+    markFinal( arguments[ arguments.length - 1 ] );
 
     // forward everything to Class
     var result = Class.apply( this, arguments );
@@ -50,7 +50,7 @@ exports = module.exports = function()
  */
 exports.extend = function()
 {
-    markFinal( arguments );
+    markFinal( arguments[ arguments.length - 1 ] );
     return Class.extend.apply( this, arguments );
 };
 
@@ -58,18 +58,12 @@ exports.extend = function()
 /**
  * Causes a definition to be flagged as final
  *
- * This function assumes the last argument to be the definition, which is the
+ * @param  {!Arguments}  dfn  suspected definition object
- * common case, and modifies the object referenced by that argument.
- *
- * @param  {!Arguments}  args  arguments to parse
  *
  * @return  {undefined}
  */
-function markFinal( args )
+function markFinal( dfn )
 {
-    // the last argument _should_ be the definition
-    var dfn = args[ args.length - 1 ];
-
     if ( typeof dfn === 'object' )
     {
         // mark as abstract
@@ -92,7 +86,7 @@ function finalOverride( obj )
     // wrap extend, applying the abstract flag
     obj.extend = function()
     {
-        markFinal( arguments );
+        markFinal( arguments[ arguments.length - 1 ] );
         return extend.apply( this, arguments );
     };
 }

lib/interface.js

@@ -184,9 +184,10 @@ var extend = ( function( extending )
         // ensure we'll be permitted to instantiate interfaces for the base
         extending = true;
 
-        var args      = Array.prototype.slice.call( arguments ),
+        var a         = arguments,
-            props     = args.pop() || {},
+            an        = a.length,
-            base      = args.pop() || Interface,
+            props     = ( ( an > 0 ) ? a[ an - 1 ] : 0 ) || {},
+            base      = ( ( an > 1 ) ? a[ an - 2 ] : 0 ) || Interface,
             prototype = new base(),
             iname     = '',
 

lib/util.js

@@ -399,7 +399,10 @@ function verifyAbstractNames( name, params )
  */
 exports.createAbstractMethod = function( def )
 {
-    var definition = Array.prototype.slice.call( arguments );
+    var dfn = [],
+        i   = arguments.length;
+
+    while ( i-- ) dfn[ i ] = arguments[ i ];
 
     var method = function()
     {
@@ -407,7 +410,7 @@ exports.createAbstractMethod = function( def )
     };
 
     exports.defineSecureProp( method, 'abstractFlag', true );
-    exports.defineSecureProp( method, 'definition', definition );
+    exports.defineSecureProp( method, 'definition', dfn );
     exports.defineSecureProp( method, '__length', arguments.length );
 
     return method;