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diff --git a/posts/elm-everything-broken.md b/posts/elm-everything-broken.md index 8fa9682..6e86cf6 100644 --- a/posts/elm-everything-broken.md +++ b/posts/elm-everything-broken.md @@ -1,33 +1,60 @@ -Title: Everything Is Broken (Elm Install Edition) +Title: Everything Is Broken (Installing Elm 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.* +*This post is a narrative rant (in the same vein of Dan Luu's ["Everything is +Broken"][danluu] post) about my problems one afternoon getting a Fancy New +Programming Language to work on my laptop. Skip to the end for my thoughts on a +solution.* -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. +[danluu]: https://danluu.com/everything-is-broken/ -So, I thought, Let's try elm! First place to head is the install page: +<br /> -[http://elm-lang.org/install]() +<div class="sidebar"> +<a href="https://www.youtube.com/watch?v=oYk8CKH7OhE"> +<img src="/static/fig/elm-evan-talk.jpg" alt="photo of E.C. giving an elm talk" width="240px" /> +</a> +</div> -Hrm, i've had painful experiences with `npm` in the past, so i'll try build from -source. +A few folks here at the [Recurse Center][rc] had nice things to say about the +[Elm programming language][rc], and after watching Evan Czaplicki's ["Let's Be +Mainstream" talk][0] I got pretty excited also. Let's try Elm! -[https://github.com/elm-lang/elm-platform]() +[rc]: https://recurse.com/ +[elm]: https://elm-lang.org +[0]: https://www.youtube.com/watch?v=oYk8CKH7OhE -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: +First I go in the front door with the [install page][install], which redirects +me to a page which instructs me to use npm. + +[install]: http://elm-lang.org/install + +Hrm, I've had painful experiences with npm in the past, and anyways, isn't +the Elm compiler implemented in Haskell? Why are they using a package +management tool for Javascript libraries for installation? No thanks, I'll +[build from source][build], following these directions from the `README.md`: + +[build]: https://github.com/elm-lang/elm-platform + + # If you are on LINUX, you need to install a dependency of elm-repl. + # Uncomment the following line and run it. + # sudo apt-get install libtinfo-dev + + # if you are on windows, or some other place without curl, just download this file manually + curl https://raw.githubusercontent.com/elm-lang/elm-platform/master/installers/BuildFromSource.hs > BuildFromSource.hs + + runhaskell BuildFromSource.hs 0.16 + +<!-- 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? --> + +Weird that these build-from-source directions involve curl-to-file magics. Why +not just clone the repo and use a Makefile, which is roughly the same number of +commands to enter? I clone repo and run the script from there instead. I'm on +Debian stable ("jessie"), so installing GHC (the most popular way to use +Haskell) is easy. I seem to have a recent version of cabal: <pre class="terminal"> bnewbold@eschaton$ cabal --version @@ -35,7 +62,7 @@ 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: +... so I think i'm ready to go ahead run the `BuildFromSource.hs` script: <pre class="terminal"> bnewbold@eschaton$ runhaskell ~/src/elm-platform/installers/BuildFromSource.hs 0.16 @@ -52,11 +79,11 @@ This could be caused by: GHCi cannot safely continue in this situation. Exiting now. Sorry. </pre> -Uh-oh! Not sure what that means. A search returns this: +Uh-oh! Not sure what that means. A search returns [a FAQ entry][faq-entry] +about "Duplicate Directions". It doesn't seem like *I* have done anything +wrong. I'll update `cabal`'s package index: -[https://wiki.haskell.org/GHC/FAQ#Duplicate_Definitions]() - -Doesn't seem like *I* have done anything wrong. I'll update `cabal`: +[faq-entry]: https://wiki.haskell.org/GHC/FAQ#Duplicate_Definitions <pre class="terminal"> bnewbold@eschaton$ cabal update @@ -66,16 +93,29 @@ 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/): +At first I assumed I was doing something wrong, or maybe the WiFi was flakey, +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. +> 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: +<div class="sidebar"> +As far as I know, the only Debian packages out of the huge stable archive which +don't receive security updates are a set of web browser, mediawiki, and all +V8/node.js packages and libraries. +</div> + +Well, wasn't even sure if updating my package index would fix the problem. I'll +give up and try npm, which these days has been [sort of +packaged][deb-node] 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: + +[deb-node]: https://www.debian.org/releases/stable/amd64/release-notes/ch-information.en.html#libv8 <pre class="terminal"> bnewbold@eschaton$ npm install elm @@ -100,6 +140,8 @@ 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 @@ -110,14 +152,23 @@ 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 $PATH), and make it executable[1]: +<div class="sidebar"> +Later I learned that I could have instead installed the nodejs-legacy +package, which just installs a symlink /usr/bin/node which points to +/usr/bin/nodejs. +</div> + +Looks like Debian wants to call node.js `nodejs` while npm/Elm expects it to +be called `node`. Ok, I create this shim named `node` in my `~/bin` directory +(which is on my `$PATH`), and make it executable: - #!/bin/sh - nodejs $* +<pre class="terminal"> +#!/bin/sh +nodejs $* +</pre> Now I can do things like: @@ -126,7 +177,7 @@ bnewbold@eschaton$ node --version v0.10.29 </pre> -Great! Now let's install elm: +Great! Now let's install Elm with npm! <pre class="terminal"> bnewbold@eschaton$ npm install elm @@ -164,27 +215,26 @@ 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 +Whoops. There is [a github issue][elm-issue] that has some tips about this: 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: +impatient at this point so I tried disabling SSL checks with npm config set ca +null`, but even then I get the same certificate error. Enough of that approach: + +[elm-issue]: https://github.com/elm-lang/elm-platform/issues/100 <pre class="terminal"> -sudo apt remove npm nodejs-legacy nodejs +sudo apt remove npm 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. +Poking around a bit more, I find the promisingly-titled "`fubar.sh`" script in +the `elm-platform` repo cloned earlier, which seems to nuke the local user's +Haskell (`cabal`) stuff (but doesn't muck with system-wide package, eg `apt` +managed GHC libraries). After running `fubar.sh` the `BuildFromSource.hs` +script seems to start working, though Hackage is still down (now, an hour after +I started this process, approaching 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 @@ -199,7 +249,7 @@ 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:: +I still get an error with compiling Elm itself though: src/Elm/Package.hs:60:25: Not in scope: `<$>' @@ -210,11 +260,13 @@ an out of date version of GHC (the Haskell compiler): I have 7.6.3 (the version that comes with Debian), and Elm wants 7.10. Fair enough: unlike a package manager, I can see how new features in the compiler would be helpful, and when I go back and look this is in the README. Fortunately there is a new version of -GHC in the jessie-backports repo, so: +GHC in the `jessie-backports` repo, so: - sudo apt install -t jessie-backports ghc +<pre class="terminal"> +sudo apt install -t jessie-backports ghc +</pre> -And now:: +And now: <pre class="terminal"> bnewbold@eschaton$ cabal --version @@ -224,7 +276,7 @@ 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 +After that, I'm miraculously able to compile. Horray! I add `~/bin/Elm-Platform/0.16/.cabal-sandbox/bin` to my `$PATH` and I can run: <pre class="terminal"> @@ -235,39 +287,92 @@ bnewbold@eschaton$ elm-repl > </pre> +Success! -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). +Throughout this debugging experience I had problems with both my external +[Lenovo Thinkpad USB keyboard][keyboard] glitching (workaround: unplug and +re-plug) and with WiFi at the Recurse Center disconnecting (workaround: reset +wifi card). Others here using GNU/Linux have the same wifi problems, but we +don't have a fix yet... something to do with wireless regulatory zones. -It's not all hard though; installing the `elm.vim` syntax highlighting plugin -is very easy, just a single `git clone` into ~/.vim/bundle/`. +It's not all pain though; installing the `elm.vim` syntax highlighting plugin +was 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`. +[keyboard]: https://www.amazon.com/Lenovo-ThinkPad-Compact-Keyboard-TrackPoint/dp/B00F3U4TQS -================ +So Now What? +---------------- -- ironically, elm packaging seems to have some nice features to prevent - breakage -- also, rust packaing seems good (link to cargo post) +TODO: dan's auto-testing tips -================ +There was a great long-form blog post by Same Boyer a few months ago +(["So You Want To Write a Package Manager"][5]) which discussed Rust's package +manager, Cargo. -**Follow up June 18th, 2016:** +[Yehuda Katz and Carl Lerche][6] designed Cargo. -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! +Ironically, given the difficulty I had installing it, the Elm language's +package manager has a great `diff` tool for checking that any changes in the +API conform the [documented][8] [semantic versioning][semver] conventions. For +[example](https://gist.github.com/badboy/a302dd0c9020e5759240): -Also, `https://status.haskell.org` seems to be broken again today, though -hackage itself seems to work. + $ elm-package diff evancz/elm-html 3.0.0 4.0.2 + Comparing evancz/elm-html 3.0.0 to 4.0.2... + This is a MAJOR change. + + ------ Changes to module Html.Attributes - MAJOR ------ + + Removed: + boolProperty : String -> Bool -> Attribute + stringProperty : String -> String -> Attribute + + + ------ Changes to module Html.Events - MINOR ------ + + Added: + type alias Options = + { stopPropagation : Bool, preventDefault : Bool } + defaultOptions : Html.Events.Options + onWithOptions : String -> Html.Events.Options -> Json.Decode.Decoder a -> (a -> Signal.Message) -> Html.Attribute + +This change information is then used to *[programatically enforce][7]* the +versioning rules and prevent a whole class of simple but annoying breakages +due to API change. + +[5]: https://medium.com/@sdboyer/so-you-want-to-write-a-package-manager-4ae9c17d9527 +[6]: https://mail.mozilla.org/pipermail/rust-dev/2014-March/009090.html +[7]: https://github.com/elm-lang/elm-package/blob/master/README.md#version-rules +[8]: https://github.com/elm-lang/elm-package/blob/master/README.md#publishing-updates +[semver]: http://semver.org/ +[appcheck]: http://www.linuxfoundation.org/collaborate/workgroups/lsb/linux-application-checker-getting-started + +<hr /> + +#### Follow up June 18th, 2016 + +A few days after writing this post, a new version of Elm (0.17) was +[released](http://elm-lang.org/blog/farewell-to-frp). The new version made some +big changes, like abandoning the [Functional Reactive Programming][frp] +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! + +[frp]: https://en.wikipedia.org/wiki/Functional_reactive_programming + +<br /> +<center style="font-size: smaller;"> +<img src="/static/fig/status_haskell_broken.png" width="600px" /> +<br /> +Also, status.haskell.org seems to be broken again today, though +the hackage website works. +</center> + +On the plus side, my USB keyboard problem seems to have been due to the cheap +random USB cable I was using. Since replacing it I haven't had the bad +flakey-ness, though now after my laptop awakes from sleep the pointer and +keyboard work but the middle mouse button ("paste" on UNIX) does not. +Workaround: plug and unplug the whole keyboard. |