The value of a little advice

[tudousi]

use while message = flash.shift() get value too cumbersome。 Some values are not my concern I just want error_message value Whether this can be req.flash('message') ?

I modified code after flash('message') the 'message' be delete, no need to manually shift.

function push(type, msg) {
  var res = this.res || this;
  var locals = res.locals.flash;
  if(!msg){
      if(typeof type === 'string' && locals.length){
          for(var i = 0, l = locals.length; i < l; i++){
              if(locals[i]['type'] === type){
                  msg = locals[i]['message'];
                  locals.splice(i, 1);
                  return msg;
              }
          }
      }
      return;
  }
  msg = {
    message: msg,
    type: type
  }

  var messages = res.locals.flash
  // do not allow duplicate flash messages
  for (var i = 0; i < messages.length; i++) {
    var message = messages[i]
    if (msg.type === message.type && msg.message === message.message) return this
  }
  messages.push(msg)
  return this
}