[`nvm`](https://github.com/creationix/nvm) (Node Version Manager) is a tool that allows you to download and install Node.js. Check if you have it installed via `nvm --version`.

    curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.26.1/install.sh | bash

[`npm`](https://www.npmjs.com) (Node Package Manager) is a tool that allows you to install javascript packages. Check if you have it installed via `npm --version`.

`npm` comes with Node.js so if you have node installed (`node --version`) you most likely have `npm` installed as well.

You don&#39;t need `nvm` unless you you want to keep multiple versions of Node.js installed on your system or if you&#39;d like to upgrade your current version.



nvm as you said is an &quot;active&quot; nodejs version manager. You can have multiple versions of node on the same machine and switch by doing &quot;nvm use version&quot;. npm respects nvm if it is present on the machine, meaning if you have 0.12.7 active and do npm install -g uuid, it will install it globally under 0.12.7 but if you switch to 4.0.0, uuid will no longer be globally available.

In any case you do not necessarily need nvm to install packages.

I see an analogy with Python for all the Python users out there.

`nvm` manages different versions of `node`. And `node` contains `npm` (package manager).

`pyenv` manages different versions of `python`. And `python` contains `pip` (package manager).

New to Go. Encountered this error and have had no luck finding the cause or the rationale for it:

If I create a struct, I can obviously assign and re-assign the values no problem:

    type Person struct {
     name string
     age int
    }

    func main() {
      x := Person{&quot;Andy Capp&quot;, 98}
      x.age = 99
      fmt.Printf(&quot;age: %d\n&quot;, x.age)
    }

but if the struct is one value in a map:

    type Person struct {
         name string
         age int
     }
    
    type People map[string]Person
    
    func main() {
      p := make(People)
      p[&quot;HM&quot;] = Person{&quot;Hank McNamara&quot;, 39}
      p[&quot;HM&quot;].age = p[&quot;HM&quot;].age + 1
      fmt.Printf(&quot;age: %d\n&quot;, p[&quot;HM&quot;].age)
    }

I get `cannot assign to p[&quot;HM&quot;].age`. That&#39;s it, no other info. http://play.golang.org/p/VRlSItd4eP

I found a way around this - creating an `incrementAge` func on Person, which can be called and the result assigned to the map key, eg `p[&quot;HM&quot;] = p[&quot;HM&quot;].incrementAge()`.

But, my question is, what is the reason for this &quot;cannot assign&quot; error, and why shouldn&#39;t I be allowed to assign the struct value directly?

Why do I get a &quot;cannot assign&quot; error when setting value to a struct as a value in a map?

I would like to simply print a &quot;hello world&quot; to the python console after /button is called by the user.

This is my naive approach:

    @app.route(&#39;/button/&#39;)
    def button_clicked():
        print &#39;Hello world!&#39;
        return redirect(&#39;/&#39;)

Background: I would like to execute other python commands from flask (not shell). &quot;print&quot; should be the easiest case.
I believe I have not understood a basic twist here.
Thanks in advance!

How to print from Flask @app.route to python console

I know **npm** is the package manager and **nvm** is the node version manager. I am currently trying to auto-install my development and production environment using Bash and forgot how I started out and in what order. After installing npm, I found our nvm was not installed. 

Do I still need to install nvm? If so, what is the benefit?

Difference between NPM and NVM

I know npm is the package manager and nvm is the node version manager. I am currently trying to auto-install my development and production environment using Bash and forgot how I started out and in what order. After installing npm, I found our nvm was not installed.
Do I still need to install nvm? If so, what is the benefit?

I&#39;m new to socket.io and have run in to something that seems pretty weird. I don&#39;t actually know the difference between `socket.emit` and `io.emit` but I can&#39;t find an explanation anywhere.

    io.on(&#39;connection&#39;, function(socket){
      io.emit(&#39;connected&#39;)  // &lt;&lt;&lt;&lt; HERE &gt;&gt; socket.emit(&#39;connected&#39;);
      socket.on(&#39;disconnect&#39;, function(){
        io.emit(&#39;disconnect&#39;)
      });
      socket.on(&#39;chat message&#39;, function(msg){
        io.emit(&#39;chat message&#39;, msg);
      });
    });
    
    server.listen(3000);

That&#39;s my server stuff however when I change the `io` to `socket` that message only gets displayed when the user who is connecting connects. `io.emit` sends the message to all users.

Maybe it&#39;s supposed to be like that or maybe its just some horrible hack? Let me know if you need the client side HTML.


io.emit vs socket.emit

I use `npm` to install some command line tools. Having the itch to always be up to date, I found the command `npm -g outdated`.

What is the difference between the columns `wanted` and `latest`?

The documentation states:

&gt; The resulting field &#39;wanted&#39; shows the latest version according to the
&gt; version specified in the package.json, the field &#39;latest&#39; the very
&gt; latest version of the package.

However I don&#39;t find it clear at all.
For example on my system I get:

    Package  Current  Wanted  Latest  Location
    cordova    5.3.1   5.3.3   5.3.1  lib
    npm        3.3.4   3.3.4   3.3.3  lib

How can `wanted` be higher than `latest`? It seems to contradict:

&gt; the field &#39;latest&#39; the very latest version of the package

Which version should I update to (I only use the command-line, not any node.js code)?


npm `wanted` vs `latest`

It seemed like a straight forward problem. But I amn&#39;t able to crack this.
Within helper1.js I would like to access foobar.json (from `config/dev/`)

    root
      -config
       --dev
        ---foobar.json
      -helpers
       --helper1.js

I couldn&#39;t get this to work https://stackoverflow.com/questions/7083045/fs-how-do-i-locate-a-parent-folder 

Any help here would be great.

NodeJS accessing file with relative path

I installed Node JS several months ago and played around a bit. Today, I wanted to start learning more about node and before coding, I decided I wanted to make sure I had the latest version.

I checked the version and it was something like v0.10.3x. I looked on the NodeJS website and it shows the latest version as v4.1.0. So I thought Woahhh! I better upgrade and I couldn&#39;t believe it moved that fast to a 4.x version in only a few months.

I spent quite some time trying to figure out how to completely uninstall node and npm because I couldn&#39;t seem to upgrade it.

Finally I got it all ripped out, then installed in on CentOS 7 using yum. I know I won&#39;t get the latest version through yum but, I figured it would be close enough.

After install, I am at v0.10.40.

I have a feeling I just don&#39;t understand something about NodeJS version numbers.

NodeJS version number confusion

I have an empty new project, when i run npm init i got a list of questions to answer, for example:
    
    name: (karma)
    version: (1.0.0)
    description:my project description
    entry point: (index.js)


I am really confused about the one that says &quot;entry point&quot;, Should this be my index.html file or my app.js or is it something else?

What is &quot;entry point&quot; in npm init

So I made the mistake of trying to get rid of all sudo dependencies. I downloaded npm as a package from the site and did a manual/global install. But it seemed as if i was always having to run with sudo...so I tried to uninstall and run with homebrew.

Now I can&#39;t get node or npm to even run...I guess I have to link with brew link them but i&#39;m getting this error:

    Could not symlink share/doc/node/gdbinit
    Target /usr/local/share/doc/node/gdbinit
    already exists. You may want to remove it:
      rm &#39;/usr/local/share/doc/node/gdbinit&#39;


I&#39;ve tried removing that:
And i&#39;ve gotten permission denied.

I have tried running brew prune.
I have tried to uninstall then reinstall using these steps:

    $ brew uninstall npm
    $ brew uninstall node
    $ npm uninstall npm -g
    $ sudo rm -rf /usr/local/lib/node_module

https://stackoverflow.com/questions/12607155/error-the-brew-link-step-did-not-complete-successfully

I am running Yosemite 10.10.5. I have git version 2.6.0 installed. My homebrew is updated. A brew doctor gives me this warning:

    Warning: You have unlinked kegs in your Cellar
    Leaving kegs unlinked can lead to build-trouble and cause brews that depend on
    those kegs to fail to run properly once built. Run `brew link` on these:
        node

 Not sure where to go from here. I&#39;m trying to lose my reliance on CodeKit and get gulp up and running.

Homebrew npm install: could not symlink

I can&#39;t get npm to work. My package.json file has

    &quot;scripts&quot;: { &quot;build&quot;: &quot;build.js&quot; }
and I have a build.js file in the same folder that just console.logs.

When I run 

    npm run build
I get the error 
    

    The system cannot execute the specified program.
	
	npm ERR! Windows_NT 6.1.7601
	npm ERR! argv &quot;C:\\Program Files\\nodejs\\node.exe&quot; &quot;C:\\Program Files\\nodejs\\node_modules\\npm\\bin\\npm-cli.js&quot; &quot;run&quot; &quot;build&quot;
	npm ERR! node v4.1.1
	npm ERR! npm  v3.3.5
	npm ERR! code ELIFECYCLE

and if I move the build.js file and change my package.json file to have a subfolder

    &quot;scripts&quot;: { &quot;build&quot;: &quot;build/build.js&quot; }

then I get the error

    &#39;build&#39; is not recognized as an internal or external command, operable program or batch file.

What&#39;s going wrong? I&#39;m copying the [example documentation][1].

  [1]: https://docs.npmjs.com/misc/scripts#examples

How do you run a js file using npm scripts?

I&#39;m getting the error shown below while trying to execute &#39;npm install&#39; command. 

&gt; Error: tunneling socket could not be established, cause=connect ECONNREFUSED 10.232.207.137:8080

What do I miss?

![screenshot][1]


  [1]: http://i.stack.imgur.com/uTzvq.png

Error &#39;tunneling socket&#39; while executing npm install

I am trying to run another NodeJS version with `nvm` but getting this error:

    $ nvm use v4.2.4

    nvm is not compatible with the npm config &quot;prefix&quot; option: 
       currently set to &quot;/Users/z/.npm-global&quot;
    Run `npm config delete prefix` or `nvm use --delete-prefix v4.2.4` to unset it.

I have my prefix set on purpose to avoid `sudo npm` (see https://docs.npmjs.com/getting-started/fixing-npm-permissions).

Is there any way I can use `nvm` without losing my prefix for globally installed packages?

nvm is not compatible with the npm config &quot;prefix&quot; option:

Is it possible to upgrade `node` right in place, instead of manually installing the latest stable version? 

I have installed [node.js][1] version `5.0` with [```nvm```][2], but now I want to update it to `5.4`. I&#39;m trying to avoid having to manually reinstall all of my global packages (*e.g.* by running `npm install -g grunt-cli bower yo yoman-angular-generator blabla blablablabla`...).


  [1]: https://nodejs.org/en/
  [2]: https://github.com/creationix/nvm

How to properly upgrade node using nvm

So I&#39;m trying to clear out older versions of node.js.

I start with:

    $ nvm ls
          v0.10.30
          v4.2.3
    -&gt;    v6.6.0
          system

I don&#39;t want the older versions, so I then do:

    $ nvm uninstall 4.2.3
    Uninstalled node v4.2.3

I then verify that it&#39;s done what I wanted, but it gives the *same* list of installed versions as before:

    $ nvm ls
          v0.10.30
          v4.2.3
    -&gt;    v6.6.0
          system

Specifically, `v4.2.3` is still there.

Any ideas what I might be doing wrong?  Any other way to force the uninstall?  I&#39;m using the Cloud 9 IDE.



nvm uninstall doesn&#39;t actually uninstall the node version

Is it possible for VS Code to use node version specified by NVM? 

I have 6.9.2 installed locally. Even after switching to another version, from the OS X terminal (not the VS Code terminal), restarting VS Code, VS Code still shows using 6.9.2.

**OS X terminal**

    MacBook-Pro-3:~ mac$ node -v
    v7.8.0

**VS Code Terminal**

    MacBook-Pro-3:QB-Invoice-API mac$ node -v
    v6.9.2

Visual Studio Code to use node version specified by NVM

For example I want to install either 7.9 or 7.10 but want to avoid Node 8 due to the `webpack node-sass` breaking bug.

When I run `brew search node` this is what I see:

&gt; ❯ brew search node
leafnode        llnode          node ✔          node-build      &gt; node@0.10       node@0.12       node@4          node@6          nodebrew        nodeenv         nodenv
caskroom/cask/node-profiler

&gt; If you meant &quot;node&quot; specifically:
It was migrated from caskroom/cask to homebrew/core.
You can access it again by running:
  brew tap homebrew/core

There is node which is checked (my current version is `v7.4.0` then `node@0.10`, `node@0.12`, `node@4` and `node@6`?

The reason I can&#39;t just fully upgrade to 8 is node-sass won&#39;t work in webpack.


----------


## Just installed NVM and got this crazy error log:

`=&gt; nvm source string already in /Users/leongaban/.zshrc
=&gt; Appending bash_completion source string to /Users/leongaban/.zshrc
npm ERR! missing: is-path-cwd@^1.0.0, required by del@3.0.0
npm ERR! missing: is-path-in-cwd@^1.0.0, required by del@3.0.0
npm ERR! missing: p-map@^1.1.1, required by del@3.0.0
npm ERR! missing: pify@^3.0.0, required by del@3.0.0
npm ERR! missing: rimraf@^2.2.8, required by del@3.0.0
npm ERR! missing: bluebird@^3.1.1, required by gulp-html-replace@1.6.2
npm ERR! missing: clone@^1.0.2, required by gulp-html-replace@1.6.2`

...

    =&gt; You currently have modules installed globally with `npm`. These will no
    =&gt; longer be linked to the active version of Node when you install a new node
    =&gt; with `nvm`; and they may (depending on how you construct your `$PATH`)
    =&gt; override the binaries of modules installed with `nvm`:


If I&#39;m reading this right, does this mean I can&#39;t use `npm` to globally install packages anymore and have to use `nvm`?

### Update

I added the export lines to my **.zshrc** bash (I don&#39;t use bash_profile)

    ❯ nvm --version
    0.33.2

Content Type	Original Author	Original Content on Stackoverflow
Question	JohnTheBeloved	View Question on Stackoverflow
Solution 1 - node.js	ThomasReggi	View Answer on Stackoverflow
Solution 2 - node.js	masimplo	View Answer on Stackoverflow
Solution 3 - node.js	azizbro	View Answer on Stackoverflow

Difference between NPM and NVM

node.js Problem Overview

node.js Solutions

Solution 1 - node.js

Solution 2 - node.js

Solution 3 - node.js

How to print from Flask @app.route to python console

Why do I get a "cannot assign" error when setting value to a struct as a value in a map?

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