I am trying to determine if there is any big differences between these two, other than being able to import with export default
by just doing:
import myItem from 'myItem';
And using export const
I can do:
import { myItem } from 'myItem';
I am wondering if there are any differences and/or use cases other than this.
It's a named export vs a default export. export const
is a named export that exports a const declaration or declarations.
To emphasize: what matters here is the export
keyword as const
is used to declare a const declaration or declarations. export
may also be applied to other declarations such as class or function declarations.
Default Export (export default
)
You can have one default export per file. When you import you have to specify a name and import like so:
import MyDefaultExport from "./MyFileWithADefaultExport";
You can give this any name you like.
Named Export (export
)
With named exports, you can have multiple named exports per file. Then import the specific exports you want surrounded in braces:
// ex. importing multiple exports:
import { MyClass, MyOtherClass } from "./MyClass";
// ex. giving a named import a different name by using "as":
import { MyClass2 as MyClass2Alias } from "./MyClass2";
// use MyClass, MyOtherClass, and MyClass2Alias here
Or it's possible to use a default along with named imports in the same statement:
import MyDefaultExport, { MyClass, MyOtherClass} from "./MyClass";
Namespace Import
It's also possible to import everything from the file on an object:
import * as MyClasses from "./MyClass";
// use MyClasses.MyClass, MyClasses.MyOtherClass and MyClasses.default here
Notes
A default export is actually a named export with the name default
so you are able to import it with a named import:
import { default as MyDefaultExport } from "./MyFileWithADefaultExport";