Handlebarsカスタムデータフォーマット、データ演算

    <tr data-id="{{id}}">
        <td width="120px">{{computeAdd udf1 udf2 udf3 udf4}}</td>
        <td width="80px">{{prettifyDate createdTime "YYYY-MM-DD"}}</td>
        <td></td>
    </tr>

Handlebars.registerHelper({
	'prettifyDate' : function(timestamp) {//     
		var format = 'YYYY-MM-DD';
		if(arguments.length > 2){
			format = arguments[1];
		}
		if(timestamp){
			return moment(new Date(timestamp)).format(format);
		} else　{
			return '';
		}
	},//         ''
	'prettifyNumber': function(number) {
		var format = '0.00', zero = true;
		if(arguments.length > 2){
			format = arguments[1];
		}
		if(arguments.length > 3){
			zero = arguments[2];
		}
		
        return (zero ? number!=null : !!number) ? numeral(number).format(format):'';
	    
	},//     
	'prettifyStr': function(s) {
        return s && s.replace(/\s/g, " " ); ;
	    
	},//         0
	'prettifyPositive': function(number) {
		var format = '0.00', zero = true;
		if(arguments.length > 2){
			format = arguments[1];
		}
		if(arguments.length > 3){
			zero = arguments[2];
		}
		
        return (zero ? number!=null&&number>0 : !!number) ? numeral(number).format(format) : '0';
	    
	},// 
	'subtract': function(number1, number2) {
		var format = '0.00';
		if(arguments.length > 3){
			format = arguments[2];
		}
		var number = number1 - number2;
		return number ? numeral(number).format(format) : '';
	},// 
	'computeAdd': function() {
		var big = 0;
		try{
			var len = arguments.length - 1;
			for(var i = 0; i < len; i++){
				if(arguments[i]){
					big = eval(big +"+"+ arguments[i]);
				}
			}
		}catch(e){
	 		throw new Error('Handlerbars Helper "computeAdd" can not deal with wrong expression:'+arguments);
	 	}
		return big;
	}
	
});

//obj       pojo 
var source   = $("#custom-template").html();
var template = Handlebars.compile(source);
var html = template(obj);