Imports and Exports

    Syntax

    We use the keyword import to load values from other JavaScript files via relative path.

    We use export to expose values for importing.

    Named imports and exports

    A single file can have multiple exports, and any subset of these can be imported simultaneously.

    Importing from modules

    There's a shorter syntax for importing 3rd party libraries: we import the name of the module's directory within node_modules (which is the name of the package in the npm package registry).

    Libraries specify a "main" file in their package.json, usually named index.js, which is what actually gets imported. E.g. assuming we had downloaded the moment library into our node_modules, we could import './node_modules/moment/index.js' with just 'moment'.

    Note: importing the path to a directory will generally import the index.js file in that directory. Some developers prefer importing from ./myDirectory rather than ./myDirectory/index.js, but these are equivalent.

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