Sorting an Array of Objects, by key

function predicateBy(prop){
   return function(a,b){
      if( a[prop] > b[prop]){
          return 1;
      }else if( a[prop] < b[prop] ){
          return -1;
      }
      return 0;
   }
}

//Usage
yourArray.sort( predicateBy("age") );
yourArray.sort( predicateBy("name") );