Javascript 意外标记'&燃气轮机'；在borswer中使用下划线.js模板时，只有Chrome可以正常工作

IE11中针对我的模板引发语法错误，如下所示：

“safari和mobile safari中出现意外令牌”

它在铬上工作得很好

我的模板如下所示。工作日的数据是二维数组，calId是字符串

var weekDaysTemplate = _.template(
    "<%" +
        "_.each(weekDays, week =>" +
        "{ %>" +
            "<div class='weekDays_row'>" + 
            "<% _.each(week, day =>" +
            "{" + 
                "if(day.notInMonth)" +
                "{ %>" +
                    "<div class='cal_day cal_notInMonth'></div>" +
                "<% }" +
                "else if(day.pastDay)" +
                "{ %>" +
                    "<div class='cal_day cal_disable'><%= day.day %></div>" +
                "<% }" +
                "else if(day.beyondLastDay)" +
                "{ %>" +
                    "<div class='cal_day cal_disable'><%= day.day %></div>" +
                "<% }" +
                "else" +
                "{ %>" +
                    "<div class='cal_day' id='<%= calId %>_cal_day_<%= day.utcTime %>' data-utc='<%= day.utcTime %>'><%= day.day %></div>" +
                "<% }" +
            "}); %>" +
            "</div>" + 
         "<% });" +
     "%>");

var weekDaysTemplate=uwk.template(
"" +
"{ %>" +
"" + 
"" +
"{" + 
“如果（日非月）”+
"{ %>" +
"" +
"" +
"" +
"" +
"" +
"" +
"" +
"" +
"" + 
"");

IE11理解ES6的

=>

功能吗？今天我碰巧发现它们不理解。