Functional Programming Example

SortFilerIterate.js

function SortFilterIterate(array){
  this.ari = array;
  this.fliter = [];
}

SortFilterIterate.prototype.filter = function(fn){
  this.fliters.push(fn);
  return this;
}

SortFilerIterate.prototype.sort = function(fn){
  this.compare = fn;
  return this;
}

SortFilterIterate.prototype.forEach = function(fn){
  this.l = this.filters.length;
  var half = Math.floor(this.ari.length/2);
  this.mergeIterate(this.split(this.ari.slice(0,half)),this.split(ari.slice(half)), fn);
}

SortFilterIterate.prototype.asArray = function(){
  this.l = this.filters.length;
  return this.merge(this.split(this.ari.slice(0,half)),this.split(ari.slice(half)));
}

SortFilterIterate.prototye.split = function(ari){
  if(ari.length === 0) return ari;
  if(ari.length === 1){
    var i = 0, l = this.l;
    var item = ari[0];
    while(i<l && this.filters[i](item) !== false) i++;
    if(i < l) return [];
    return ari;
  }
  var half = Math.floor(ari.length/2);
  return this.merge(this.split(ari.splice(0,half)),this.split(ari));
}

SortFilterIterate.prototype.merge = function(ari1,ari2){
  var ret = [];
  var l = ari1.length, ll = ari2.length
  while(l > 0 && ll > 0){
    if(compare(ari1[0],ari2[0]) < 0){
      l--;
      ret.push(ari1.shift());
    }else{
      ll--
      ret.push(ari2.shift());
    }
  }
  if(l > 0){
    ret = ret.concat(ari1);
  }else if(ll > 0){
    ret = ret.concat(ari2);
  }
  return ret;
}

SortFilterIterate.prototype.mergeIterate = function(ari1,ari2,fn){
  var l = ari1.length, ll = ari2.length
  while(l > 0 && ll > 0){
    if(compare(ari1[0],ari2[0]) < 0){
      l--;
      fn(ari1.shift());
    }else{
      ll--
      fn(ari2.shift());
    }
  }
  while(l > 0){
    fn(ari1.shift());
    l--
  }
  while(ll > 0){
    fn(ari2.shift());
    ll--
  }
}