Skip to content
This repository has been archived by the owner on Apr 8, 2022. It is now read-only.

Latest commit

 

History

History
290 lines (201 loc) · 9.7 KB

README.md

File metadata and controls

290 lines (201 loc) · 9.7 KB

This repository is archived


Simple Elixir Version Management: exenv

exenv lets you easily switch between multiple versions of Elixir. It's simple, unobtrusive, and follows the UNIX tradition of single-purpose tools that do one thing well.

exenv is a Elixir version of rbenv and used denv as a reference. Thanks to @sstephenson and @repeatedly.

exenv does…

  • Let you change the global Elixir version on a per-user basis.
  • Provide support for per-project Elixir versions.
  • Allow you to override the Elixir version with an environment variable.

Table of Contents

1 How It Works

exenv operates on the per-user directory ~/.exenv. Version names in exenv correspond to subdirectories of ~/.exenv/versions. For example, you might have ~/.exenv/versions/0.6.0 and ~/.exenv/versions/0.7.0.

Each version is a working tree with its own binaries, like ~/.exenv/versions/0.6.0/bin/elixir and ~/.exenv/versions/0.7.0/bin/iex. exenv makes shim binaries for every such binary across all installed versions of Elixir.

These shims are simple wrapper scripts that live in ~/.exenv/shims and detect which Elixir version you want to use. They insert the directory for the selected version at the beginning of your $PATH and then execute the corresponding binary.

Because of the simplicity of the shim approach, all you need to use exenv is ~/.exenv/shims in your $PATH.

2 Installation

2.1 Basic GitHub Checkout

This will get you going with the latest version of exenv and make it easy to fork and contribute any changes back upstream.

  1. Check out exenv into ~/.exenv.

     $ cd
     $ git clone git://github.com/mururu/exenv.git .exenv
    
  2. Add ~/.exenv/bin to your $PATH for access to the exenv command-line utility.

     $ echo 'export PATH="$HOME/.exenv/bin:$PATH"' >> ~/.bash_profile
    

    Zsh note: Modify your ~/.zshenv file instead of ~/.bash_profile.

  3. Add exenv init to your shell to enable shims and autocompletion.

     $ echo 'eval "$(exenv init -)"' >> ~/.bash_profile
    

    Zsh note: Modify your ~/.zshenv file instead of ~/.bash_profile.

  4. Restart your shell so the path changes take effect. You can now begin using exenv.

     $ exec $SHELL
    
  5. Install Elixir versions into ~/.exenv/versions. For example, to install Elixir 0.13.3, download and unpack the source, then run:

     $ wget https://github.com/elixir-lang/elixir/archive/v0.13.3.zip
     $ unzip v0.13.3.zip
     $ mv elixir-0.13.3/ ~/.exenv/versions/0.13.3
    
  6. Rebuild the shim binaries. You should do this any time you install a new Elixir binary (for example, when installing a new Elixir version, or when installing a gem that provides a binary).

     $ exenv rehash
    

2.1.1 Upgrading

If you've installed exenv using the instructions above, you can upgrade your installation at any time using git.

To upgrade to the latest development version of exenv, use git pull:

$ cd ~/.exenv
$ git pull

To upgrade to a specific release of exenv, check out the corresponding tag:

$ cd ~/.exenv
$ git fetch
$ git tag
v0.1.0
v0.1.1
v0.1.2
v0.2.0
$ git checkout v0.2.0

2.2 Neckbeard Configuration

Skip this section unless you must know what every line in your shell profile is doing.

exenv init is the only command that crosses the line of loading extra commands into your shell. Coming from rvm, some of you might be opposed to this idea. Here's what exenv init actually does:

  1. Sets up your shims path. This is the only requirement for exenv to function properly. You can do this by hand by prepending ~/.exenv/shims to your $PATH.

  2. Installs autocompletion. This is entirely optional but pretty useful. Sourcing ~/.exenv/completions/exenv.bash will set that up. There is also a ~/.exenv/completions/exenv.zsh for Zsh users.

  3. Rehashes shims. From time to time you'll need to rebuild your shim files. Doing this on init makes sure everything is up to date. You can always run exenv rehash manually.

  4. Installs the sh dispatcher. This bit is also optional, but allows exenv and plugins to change variables in your current shell, making commands like exenv shell possible. The sh dispatcher doesn't do anything crazy like override cd or hack your shell prompt, but if for some reason you need exenv to be a real script rather than a shell function, you can safely skip it.

Run exenv init - for yourself to see exactly what happens under the hood.

3 Usage

Like git, the exenv command delegates to subcommands based on its first argument. The most common subcommands are:

3.1 exenv global

Sets the global version of Elixir to be used in all shells by writing the version name to the ~/.exenv/version file. This version can be overridden by a per-project .exenv-version file, or by setting the EXENV_VERSION environment variable.

$ exenv global 0.7.0

The special version name system tells exenv to use the system Elixir (detected by searching your $PATH).

When run without a version number, exenv global reports the currently configured global version.

3.2 exenv local

Sets a local per-project Elixir version by writing the version name to an .exenv-version file in the current directory. This version overrides the global, and can be overridden itself by setting the EXENV_VERSION environment variable or with the exenv shell command.

$ exenv local 0.6.0

When run without a version number, exenv local reports the currently configured local version. You can also unset the local version:

$ exenv local --unset

3.3 exenv shell

Sets a shell-specific Elixir version by setting the EXENV_VERSION environment variable in your shell. This version overrides both project-specific versions and the global version.

$ exenv shell 0.7.0

When run without a version number, exenv shell reports the current value of EXENV_VERSION. You can also unset the shell version:

$ exenv shell --unset

Note that you'll need exenv's shell integration enabled (step 3 of the installation instructions) in order to use this command. If you prefer not to use shell integration, you may simply set the EXENV_VERSION variable yourself:

$ export EXENV_VERSION=0.6.0

3.4 exenv versions

Lists all Elixir versions known to exenv, and shows an asterisk next to the currently active version.

$ exenv versions
  0.5.0
* 0.6.0
  0.7.0

3.5 exenv version

Displays the currently active Elixir version, along with information on how it was set.

$ exenv version
0.7.0 (set by /Volumes/37signals/basecamp/.exenv-version)

3.6 exenv rehash

Installs shims for all Elixir binaries known to exenv (i.e., ~/.exenv/versions/*/bin/*). Run this command after you install a new version of Elixir.

$ exenv rehash

3.7 exenv which

Displays the full path to the binary that exenv will execute when you run the given command.

$ exenv which iex
/Users/sam/.exenv/versions/0.7.0/bin/iex

3.8 exenv install

Using elixir-build, you can install Elixir automatically. Please see here(elixir-build) for more details.

4 Development

The exenv source code is hosted on GitHub. It's clean, modular, and easy to understand, even if you're not a shell hacker.

Please feel free to submit pull requests and file bugs on the issue tracker.

4.1 Version History

0.1.0 (November 10, 2012)

Fork rbenv

4.2 License

(The MIT license)

Copyright (c) 2011 Sam Stephenson, Yuki Ito

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.