Vue computed calculation attribute when the dependent property is updated, the calculation property is not executed?

computed: {
    comp: function () {
        return () => import(`./component/item${this.formItem.item_type}.form`);
    }
},

when I switch the value of this.formItem.item_type, comp is not triggered 

computed: {
    comp: function () {
        console.log(this.formItem.item_type)
        return () => import(`./component/item${this.formItem.item_type}.form`);
    }
},

when I add console.log (this.formItem.item_type), it triggers normally, but comment out doesn"t trigger normally. Why?

in addition: I use watch to monitor normal 

watch:{
    "formItem.item_type": function (val, oldVal) {
        this.comp = () => import(`./component/item${this.formItem.item_type}.form`);
    }
},

supplement this.formItem objects

clipboard.png

Vue.js
Mar.23,2021

first check whether this.formItem.item_type is responsive. Expand to this point with the developer tool, if it is (.) or if there is a light-colored get/set below, otherwise, this variable is not observed, so there is no response.

because only if you access the corresponding variable in the evaluation property, the calculation property can form a dependence on it. 

comp: function () {
    // ,  comp 
    this.formItem.item_type;
  
    return () => import(`./component/item${this.formItem.item_type}.form`);
}

Previous: About the difference between alert (1) and alert`1`?

Next: In the following case, X is not assigned, so why return 6?

css mysql arrays josn react html typescript webpack npm sass R objective-c .net sql-server jquery python-3.x angularjs django angular excel regex iphone ajax linux xml pandas vba spring database wordpress string wpf xcode windows bash postgresql oracle multithreading eclipse list firebase algorithm macos forms image scala visual-studio azure bootstrap spring-boot react-native python-2.7 docker performance function winforms matlab powershell apache dataframe api sqlite numpy rest shell selenium flutter dart maven loops qt swing android-studio csv express file class tensorflow sorting codeigniter perl
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b3eed4-2bbcd.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b3eed4-2bbcd.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
Need Help?