Useful sortBy function in JavaScript

JS-sortBy

	var sort_by = function(field, reverse, primer){

	   var key = function (x) {return primer ? primer(x[field]) : x[field]};
	
	   return function (a,b) {
	       var A = key(a), B = key(b);
	       return (A < B ? -1 : (A > B ? 1 : 0)) * [1,-1][+!!reverse];                  
	   }
	};