What package version does @next specify for npm?

Question

What version of package foo will this command install?

npm install foo@next 

The package.json and semver docs don't mention next.

Answer 1

next is a version or tag published in your reference npm registry

npm install installs a package.

A package is:  ... d) a <name>@<version> that is published on the registry (see npm-registry) with (c) e) a <name>@<tag> (see npm-dist-tag) that points to (d) ... 

You can view the version that each dist-tag points to by running the following commands:

npm view <package_name> dist-tags npm dist-tags ls <package_name> 

e.g. for the react npm package:

npm view react dist-tags 

Output:

{   latest: '17.0.2',   next: '18.0.0-rc.0-next-3dc41d8a2-20211223',   experimental: '0.0.0-experimental-3dc41d8a2-20211223',   beta: '18.0.0-beta-24dd07bd2-20211208',   rc: '18.0.0-rc.0' } 

Source

Answer 2

Next is tag. look at the below possible commands.

A tag can be used when installing packages as a reference to a version instead of using a specific version number:

npm install [<@scope>/]<name> npm install [<@scope>/]<name>@<tag> npm install [<@scope>/]<name>@<version> npm install [<@scope>/]<name>@<version range> 

How its added in package? See dist-tag

npm dist-tag add <pkg>@<version> [<tag>] npm dist-tag rm <pkg> <tag> npm dist-tag ls [<pkg>] 

Check - https://docs.npmjs.com/cli/dist-tag