Questions about the cast of js empty object types in Chrome

when an empty object is summed with another data, such as 

{} + []
The empty object in front of

is generally treated as an empty block of code and becomes 

+ [] // 0

so when empty objects and empty objects are summed 

{} + {}

an empty object is treated as a code block is equal to 

+ {}

the result should be NaN.

but in Chrome 

{} + {} // "[object Object][object Object]"

obviously the first empty object is not treated as a code block.

in other browsers such as Firefox or IE 

{} + {}

the results are all NaN.

I don"t quite understand why it is different in

Chrome.

Javascript
Apr.20,2022

because {} + {} has different parsing methods 

  1.    {
   }
   +{}

    is preceded by an empty code block

  2. is parsed as an object before and after, and finally, the respective toString methods are called to concatenate strings
    3. .

to avoid the above ambiguity, you can use ({} + {}) to achieve consistency

.

Previous: Under what circumstances can Angular6 QueryList query the data?

Next: Vue project npm run build reported an error

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
© 2021 CodesHelper
Advertising Contact us About us
Menu