Array.prototype.unique

Array.prototype.unique = function(a){
return function(){return this.filter(a)}}(function(a,b,c){return c.indexOf(a,b+1)<0
});






 Benchmark.prototype.setup = function() {
    Array.prototype.contains = function(v) {
        for(var i = 0; i < this.length; i++) {
            if(this[i] === v) return true;
        }
        return false;
    };

    Array.prototype.unique = function() {
        var arr = [];
        for(var i = 0; i < this.length; i++) {
            if(!arr.contains(this[i])) {
                arr.push(this[i]);
            }
        }
        return arr;
    }

    //if you need a 'shim':
    Array.prototype.filter= Array.prototype.filter || function(fun, scope){
        var T= this, A= [], i= 0, itm, L= T.length;
        if(typeof fun== 'function'){
            while(i<L){
                if(i in T){
                    itm= T[i];
                    if(fun.call(scope, itm, i, T)) A[A.length]= itm;
                }
                ++i;
            }
        }
        return A;
    }
     Array.prototype.indexOf= Array.prototype.indexOf || function(what, i){
            if(!i || typeof i!= 'number') i= 0;
            var L= this.length;
            while(i<L){
                if(this[i]=== what) return i;
                ++i;
            }
            return -1;
        }

    var duplicates = [1,3,4,2,1,2,3,8];

    // kodono.info
    Array.prototype.unique2=function(){var o={},i,l=this.length,r=[];for(i=0;i<l;i++)o[this[i]]=this[i];for(i in o)r.push(o[i]);return r}
  };






var unique= array1.filter(function(itm, i){
    return array1.indexOf(itm)== i;
    // returns true for only the first instance of itm
});


//if you need a 'shim':
Array.prototype.filter= Array.prototype.filter || function(fun, scope){
    var T= this, A= [], i= 0, itm, L= T.length;
    if(typeof fun== 'function'){
        while(i<L){
            if(i in T){
                itm= T[i];
                if(fun.call(scope, itm, i, T)) A[A.length]= itm;
            }
            ++i;
        }
    }
    return A;
}
 Array.prototype.indexOf= Array.prototype.indexOf || function(what, i){
        if(!i || typeof i!= 'number') i= 0;
        var L= this.length;
        while(i<L){
            if(this[i]=== what) return i;
            ++i;
        }
        return -1;
    }