FastSolidArray.js

(function($G)
{
  var _lengthGetter = function()
  {
    var b = -1;
    var i;
    
    for( ;; )
    {
      i = 1;
      
      while(this.hasOwnProperty(b + i))
        i <<= 1;
        
      if(i == 1)
        break;
      
      b += i >>= 1;  

      // 3 steps back
      if(i && this.hasOwnProperty(b + (i >>= 1)))
        b += i;

      if(i && this.hasOwnProperty(b + (i >>= 1)))
        b += i;

      if(i && this.hasOwnProperty(b + (i >>= 1)))
        b += i;
    }
    
    return b + 1;
  }
  
  var _lengthSetter = function(nLen)
  {
    var cLen = +this.length;
    
    if(cLen < nLen)
    {
      var i = cLen - 1, u = undefined; while(++i < nLen)
        this[i] = undefined;
    }
    else
    {
      var i = +nLen; while(--i >= cLen)
        delete this[i];
    }
  };
  
  var FastSolidArray;
  
  if(Object.defineProperty)
  {  
    var lengthProp =   
    {
      get: _lengthGetter,
      set: _lengthSetter,
      configurable: false,
      enumerable: false
    };

    FastSolidArray = function(len)
    {
      Object.defineProperty(
        this,
        'length',
        lengthProp
      );
      
      if(len != null)
        this.length = len;
    };
  }  
  else if({}.__defineGetter__ && {}.__defineSetter__)  
  {
    FastSolidArray = function(len)
    {
      this.__defineGetter__('length', _lengthGetter);
      this.__defineSetter__('length', _lengthSetter);
      
      if(len != null)
        this.length = len;
    };
  }
  
  FastSolidArray.prototype = new Array();
  FastSolidArray.prototype.constructor = FastSolidArray;

  $G.FastSolidArray = FastSolidArray;
})(this);

// test
(function($G)
{
  var _fill = function(a, c)
  {
    var i = a.length >>> 0;
    
    while(i--)
      a[i] = c;
  };
  
  var m = 1000;
  
  _speedTest(
    [
      function(n)
      {
        var a = new Array(m);
        
        var i = n >>> 0; while(i--)
          _fill(a, 1);
      },
      function(n)
      {
        var a = new FastSolidArray(m);
        
        var i = n >>> 0; while(i--)
          _fill(a, 1);
      }
    ],
    1000
  );
})(this);

/*
opera 10.60 

m = 1000000
0: 5484 ms
1: 5080 ms

m = 100000
0: 4869 ms
1: 3225 ms

m = 10000
0: 3009 ms
1: 2595 ms

m = 1000
0: 3053 ms
1: 3143 ms

m = 100
0: 4981 ms
1: 7834 ms

*/  (function($G)
{
  var _lengthGetter = function()
  {
    var b = -1;
    var i;
    
    for( ;; )
    {
      i = 1;
      
      while(this.hasOwnProperty(b + i))
        i <<= 1;
        
      if(i == 1)
        break;
      
      b += i >>= 1;  

      // 3 steps back
      if(i && this.hasOwnProperty(b + (i >>= 1)))
        b += i;

      if(i && this.hasOwnProperty(b + (i >>= 1)))
        b += i;

      if(i && this.hasOwnProperty(b + (i >>= 1)))
        b += i;
    }
    
    return b + 1;
  }
  
  var _lengthSetter = function(nLen)
  {
    var cLen = +this.length;
    
    if(cLen < nLen)
    {
      var i = cLen - 1, u = undefined; while(++i < nLen)
        this[i] = undefined;
    }
    else
    {
      var i = +nLen; while(--i >= cLen)
        delete this[i];
    }
  };
  
  var FastSolidArray;
  
  if(Object.defineProperty)
  {  
    var lengthProp =   
    {
      get: _lengthGetter,
      set: _lengthSetter,
      configurable: false,
      enumerable: false
    };

    FastSolidArray = function(len)
    {
      Object.defineProperty(
        this,
        'length',
        lengthProp
      );
      
      if(len != null)
        this.length = len;
    };
  }  
  else if({}.__defineGetter__ && {}.__defineSetter__)  
  {
    FastSolidArray = function(len)
    {
      this.__defineGetter__('length', _lengthGetter);
      this.__defineSetter__('length', _lengthSetter);
      
      if(len != null)
        this.length = len;
    };
  }
  
  FastSolidArray.prototype = new Array();
  FastSolidArray.prototype.constructor = FastSolidArray;

  $G.FastSolidArray = FastSolidArray;
})(this);

// test
(function($G)
{
  var _fill = function(a, c)
  {
    var i = a.length >>> 0;
    
    while(i--)
      a[i] = c;
  };
  
  var m = 1000;
  
  _speedTest(
    [
      function(n)
      {
        var a = new Array(m);
        
        var i = n >>> 0; while(i--)
          _fill(a, 1);
      },
      function(n)
      {
        var a = new FastSolidArray(m);
        
        var i = n >>> 0; while(i--)
          _fill(a, 1);
      }
    ],
    1000
  );
})(this);

/*
opera 10.60 

m = 1000000
0: 5484 ms
1: 5080 ms

m = 100000
0: 4869 ms
1: 3225 ms

m = 10000
0: 3009 ms
1: 2595 ms

m = 1000
0: 3053 ms
1: 3143 ms

m = 100
0: 4981 ms
1: 7834 ms

*/