NPM造成全球混乱

Question

npm install css-sprite --save

npm install css-sprite -g

What does 2 different command above do? I know -g is global, but why do you want it to be global? What's --save?

Answer 1

• npm install MODULE --save will add the module's name and information directly into your package.json file. It is a shortcut from writing the dependency first in your package.json and then doing npm install (which reads the file and installs all dependencies).

• npm install MODULE -g will make sure the module is accessible everywhere in your system, not just in your project's directory. The purpose of this, is that some modules can be used in a "standalone" way, without NodeJS. For example, module Jade is a template engine for HTML. I write all my HTML files in Jade (syntax), and then I call jade myfile.jade to render HTML files. I can only call jade freely in the console after installing it globally through npm.

Answer 2

https://docs.npmjs.com/cli/install

According to the npm documentation :

--save: Package will appear in your dependencies.

The --global argument will cause npm to install the package globally rather than locally.

--save will modify the package.json and add the dependencies in it.

--global will install the module as a global module. Every nodejs application on your machine will have this module. On most computers, the global folder of npm is in the PATH. So when you install a module as --global, you can use in a command line.