bindtap="__e" ,下划线e是函数名称吗，可是没找到这样函数名称？

<view class="btn-group">

        <button bindgetphonenumber="__e" class="wx-login-btn" data-event-opts="{{[ [ 'getphonenumber',[ [ 'decryptPhoneNumber',['$event'] ] ] ] ]}}" openType="getPhoneNumber">微信一键登录</button>

        <button bindtap="__e" class="phone-login-btn" data-event-opts="{{[ [ 'tap',[ [ 'goPhoneLogin',['$event'] ] ] ] ]}}" hidden="{{!!hidePhoneAuth}}">已有账号,手机号登录</button>

    </view>