path: root/posts/elm-everything-broken.md

Title: Everything Is Broken (Elm Install Edition)
Author: bnewbold
Date: 2016-05-06
Status: draft

*This post is mostly a rant about my problems getting a fancy new programming
language to work on my laptop.*

A few folks at the Recurse Center had nice things to say about the [Elm
programming language](https://elm-lang.org), and after watching Evan
Czaplicki's ["Let's Be Mainstream" talk](https://www.youtube.com/watch?v=oYk8CKH7OhE)
I got pretty excited also.

So, I thought, Let's try elm! First place to head is the install page:

[http://elm-lang.org/install]()

Hrm, i've had painful experiences with `npm` in the past, so i'll try build from
source.

[https://github.com/elm-lang/elm-platform]()

Weird, build from source directions involve some curl-to-file thing. Why not
just clone the repo and have a makefile? If you don't know how to clone a repo,
are you really going to know how to get cabal set up, open a terminal and paste
a command, etc? Anyways, I clone repo and run the script from there instead.
I'm on debian stable (jessie), so installing Haskell (GHC) is easy, and there
is a good chance things will just work because this Debian stable is a
reasonably popular developer platform. I seem to have a recent version of
cabal:

<pre class="terminal">
bnewbold@eschaton$ cabal --version
cabal-install version 1.20.0.3
using version 1.20.0.2 of the Cabal library 
</pre>

so I run the `BuildFromSource.hs` script:

<pre class="terminal">
bnewbold@eschaton$ runhaskell ~/src/elm-platform/installers/BuildFromSource.hs 0.16

GHCi runtime linker: fatal error: I found a duplicate definition for symbol
_hs_bytestring_long_long_uint_hex
whilst processing object file
/home/bnewbold/.cabal/lib/x86_64-linux-ghc-7.6.3/bytestring-0.10.6.0/HSbytestring-0.10.6.0.o
This could be caused by:
* Loading two different object files which export the same symbol
* Specifying the same object file twice on the GHCi command line
* An incorrect `package.conf' entry, causing some object to be
    loaded twice.
GHCi cannot safely continue in this situation.  Exiting now.  Sorry.
</pre>

Uh-oh! Not sure what that means. A search returns this:

[https://wiki.haskell.org/GHC/FAQ#Duplicate_Definitions]()
    
Doesn't seem like *I* have done anything wrong. I'll update `cabal`:

<pre class="terminal">
bnewbold@eschaton$ cabal update
Downloading the latest package list from hackage.haskell.org
cabal: Failed to download
http://hackage.haskell.org/packages/archive/00-index.tar.gz : ErrorMisc "Error
HTTP code: 502"
</pre>

I assumed I was doing something wrong, but it turns out that the Hackage
package repository [is down](https://status.haskell.org/):

    hackage.haskell.org down    Full Service Disruption
    [Investigating] The hackage server is in an out of memory condition. We're investigating.

Hrm. Well, wasn't even sure if that would fix the problem. I'll give up and try
`npm`, which these days has been "partially" packaged in Debian. I'll just
uninstall `npm` when i'm done installing Elm. I install with apt (which pulls
in a huge list of nodejs packages), but then can finally run:

<pre class="terminal">
bnewbold@eschaton$ npm install elm
|
> elm@0.16.0 install /home/bnewbold/bin/node_modules/elm
> node install.js

sh: 1: node: not found
npm WARN This failure might be due to the use of legacy binary "node"
npm WARN For further explanations, please read
/usr/share/doc/nodejs/README.Debian

npm ERR! elm@0.16.0 install: `node install.js`
npm ERR! Exit status 127
npm ERR! 
npm ERR! Failed at the elm@0.16.0 install script.
npm ERR! This is most likely a problem with the elm package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR!     node install.js
npm ERR! You can get their info via:
npm ERR!     npm owner ls elm
npm ERR! There is likely additional logging output above.

npm ERR! System Linux 3.16.0-4-amd64
npm ERR! command "/usr/bin/nodejs" "/usr/bin/npm" "install" "elm"
npm ERR! cwd /home/bnewbold/bin
npm ERR! node -v v0.10.29
npm ERR! npm -v 1.4.21
npm ERR! code ELIFECYCLE
npm ERR! 
npm ERR! Additional logging details can be found in:
npm ERR!     /home/bnewbold/bin/npm-debug.log
npm ERR! not ok code 0
</pre>

Looks like Debian wants to call node.js `nodejs` while npm/Elm expects it to be
called `node`. Ok, I create this shim named `node` in my ~/bin directory (which
is on my $PATH), and make it executable[1]:

    #!/bin/sh
    nodejs $*

Now I can do things like:

<pre class="terminal">
bnewbold@eschaton$ node --version
v0.10.29
</pre>

Great! Now let's install elm:

<pre class="terminal">
bnewbold@eschaton$ npm install elm

> elm@0.16.0 install /home/bnewbold/bin/node_modules/elm
> node install.js

Downloading Elm Reactor assets from https://dl.bintray.com/elmlang/elm-platform/0.16.0/elm-reactor-assets.tar.gz
Error communicating with URL https://dl.bintray.com/elmlang/elm-platform/0.16.0/linux-x64.tar.gz Error: CERT_UNTRUSTED
npm WARN This failure might be due to the use of legacy binary "node"
npm WARN For further explanations, please read
/usr/share/doc/nodejs/README.Debian

npm ERR! elm@0.16.0 install: `node install.js`
npm ERR! Exit status 1
npm ERR! 
npm ERR! Failed at the elm@0.16.0 install script.
npm ERR! This is most likely a problem with the elm package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR!     node install.js
npm ERR! You can get their info via:
npm ERR!     npm owner ls elm
npm ERR! There is likely additional logging output above.

npm ERR! System Linux 3.16.0-4-amd64
npm ERR! command "/usr/bin/nodejs" "/usr/bin/npm" "install" "elm"
npm ERR! cwd /home/bnewbold/bin
npm ERR! node -v v0.10.29
npm ERR! npm -v 1.4.21
npm ERR! code ELIFECYCLE
npm ERR! 
npm ERR! Additional logging details can be found in:
npm ERR!     /home/bnewbold/bin/npm-debug.log
npm ERR! not ok code 0
</pre>

This github issue seems to have some tips:

    https://github.com/elm-lang/elm-platform/issues/100

The recommended solutions online are basically "upgrade node.js and npm" or
"disable SSL security". That doesn't sound great, but i'm feeling very
impatient at this point so I try disabling SSL checks with `npm config set ca
null`, but even with that I get the same certificate error. Enough of that
approach:

<pre class="terminal">
sudo apt remove npm nodejs-legacy nodejs
rm ~/bin/node
</pre>

Poking around a bit more, I find the `fubar.sh` script in the `elm-platform`
repo, which seems to nuke the local user's Haskell (cabal) stuff (not
system-wide package, eg apt managed GHC libraries). After running that the
`BuildFromSource.hs` seems to start working, though Hackage is still down (now,
an hour after I started this process, at 5 hours total downtime), so I can't
install dependencies.

I search for a hackage mirror and find that [FPComplete runs
one](https://www.fpcomplete.com/blog/2015/03/hackage-mirror).  In addition to
their directions I had to set `remote-repo-cache` in my `~/.cabal/config`, like
so:

    remote-repo: hackage.fpcomplete.com:http://hackage.fpcomplete.com/
    remote-repo-cache: /home/bnewbold/.cabal/packages-fpcomplete

After that I `cabal update` and run the `BuildFromSource.hs` script again. It
fails to build the dependency `websockets-snap`, but I try installing that
regularly (`cabal install websockets-snap`) and that works, then all the
dependencies with BuildFromSource.hs build. Yay!

I still get an error with compiling Elm itself though::

    src/Elm/Package.hs:60:25:
        Not in scope: `<$>'
        Perhaps you meant `</>' (imported from System.FilePath)

It [sounds like](https://github.com/elm-lang/elm-platform/issues/30) I am using
an out of date version of GHC (the Haskell compiler): I have 7.6.3 (the version
that comes with Debian), and Elm wants 7.10. Fair enough: unlike a package
manager, I can see how new features in the compiler would be helpful, and when
I go back and look this is in the README. Fortunately there is a new version of
GHC in the jessie-backports repo, so:

    sudo apt install -t jessie-backports ghc
   
And now::

<pre class="terminal">
bnewbold@eschaton$ cabal --version
cabal-install version 1.22.6.0
using version 1.22.5.0 of the Cabal library 
bnewbold@eschaton$ ghc --version
The Glorious Glasgow Haskell Compilation System, version 7.10.3
</pre>

After that, i'm miraculously able to compile. Horray! I add
`~/bin/Elm-Platform/0.16/.cabal-sandbox/bin` to my `$PATH` and I can run:

<pre class="terminal">
bnewbold@eschaton$ elm-repl 
---- elm repl 0.16.0 -----------------------------------------------------------
:help for help, :exit to exit, more at <https://github.com/elm-lang/elm-repl>
--------------------------------------------------------------------------------
> 
</pre>


Also, through out this debugging experience i've had problems with my external
Lenovo Thinkpad USB keyboard glitching (workaround: unplug and replug) and with
WiFi here at the Recurse Center disconnecting (other have the same problem,
something to do with wireless regulatory zones, but we don't have a fix yet).

It's not all hard though; installing the `elm.vim` syntax highlighting plugin
is very easy, just a single `git clone` into ~/.vim/bundle/`.

[1]: later I learn that I could instead have installed the `nodejs-legacy`
     package, which just installs a symlink `/usr/bin/node` which points to
     `/usr/bin/nodejs`.

================

- ironically, elm packaging seems to have some nice features to prevent
  breakage
- also, rust packaing seems good (link to cargo post)

================

**Follow up June 18th, 2016:**

A new version of Elm (0.17) was 
[released](http://elm-lang.org/blog/farewell-to-frp)
was released a few days after writing this post. The new version made some big
changes, like abandoning the Functional Reactive paradigm. I found that many of
the new tutorials weren't working with my 0.16 install, so I tried to upgrade.
After an hour or two of following the directions above, I gave up and installed
`npm` on a temporary Debian unstable ("sid") virtual machine. Once I added a
`node` symlink to `nodejs`, I was able to install `elm` with `npm` and develop
remotely using `screen` and `elm-react`. Frustrating!

Also, `https://status.haskell.org` seems to be broken again today, though
hackage itself seems to work.