Simple Mono Parallel Environment Manager: mope

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

Features

mope does...

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

mope does not...

• Need to be loaded into your shell. Instead, mope's shim approach works by adding a directory to your $PATH.
• Override shell commands like cd. That's dangerous and error-prone.
• Have a configuration file. There's nothing to configure except which version of Mono you want to use.
• Install Mono. You can build and install Mono yourself, or use mono-build to automate the process.
• Require changes to Mono libraries for compatibility. The simplicity of mope means as long as it's in your $PATH, nothing else needs to know about it.
• Prompt you with warnings when you switch to a project. Instead of executing arbitrary code, mope reads just the version name from each project. There's nothing to "trust."

Table of Contents

• 1 How It Works
• 2 Installation
  • 2.1 Basic GitHub Checkout
    • 2.1.1 Upgrading
  • 2.2 Neckbeard Configuration
• 3 Usage
  • 3.1 mope global
  • 3.2 mope local
  • 3.3 mope shell
  • 3.4 mope versions
  • 3.5 mope version
  • 3.6 mope rehash
  • 3.7 mope which
  • 3.8 mope whence
• 4 Development
  • 4.1 Version History
  • 4.2 Thanks
  • 4.3 License

1 How It Works

mope operates on the per-user directory ~/.mope. Version names in mope correspond to subdirectories of ~/.mope/versions. For example, you might have ~/.mope/versions/2.10.9 and ~/.mope/versions/2.11.0.

Each version is a working tree with it's own binaries, like ~/.mope/versions/2.10.9/bin/mono and ~/.mope/versions/2.10.9/bin/csharp. mope makes shim binaries for every such binary across all installed versions of Mono.

These shims are simple wrapper scripts that live in ~/.mope/shims and detect which Mono 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 mope is ~/.mope/shims in your $PATH.

2 Installation

2.1 Basic GitHub Checkout

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

1. Check out mope into ~/.mope.

    $ cd
    $ git clone git://github.com/dragan/mope.git .mope
   

2. Add ~/.mope/bin to your $PATH for access to the mope command-line utility.

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

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

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

    $ echo 'eval "$(mope 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 mope.

    $ exec $SHELL
   

5. Install Mono versions into ~/.mope/versions. For example, to install Mono 2.11.0, download and unpack the source, then run:

    $ ./configure --prefix=$HOME/.mope/versions/2.11.0
    $ make
    $ make install
   

   The mono-build project provides a mope install command that simplifies the process of installing new Mono versions to:

    $ mope install 2.11.0
   

6. Rebuild the shim binaries. You should do this any time you install new Mono binaries (for example, when installing a new Mono version).

    $ mope rehash
   

   note: mope install will automatically do this for you.

2.1.1 Upgrading

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

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

$ cd ~/.mope
$ git pull

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

$ cd ~/.mope
$ 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.

mope init is the only command that crosses the line of loading extra commands into your shell. Here's what mope init actually does:

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

2. Installs autocompletion. This is entirely optional but pretty useful. Sourcing ~/.mope/completions/mope.bash will set that up. There is also a ~/.mope/completions/mope.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 mope rehash manually.

4. Installs the sh dispatcher. This bit is also optional, but allows mope and plugins to change variables in your current shell, making commands like mope 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 mope to be a real script rather than a shell function, you can safely skip it.

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

3 Usage

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

3.1 mope global

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

$ mope global 2.10.9

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

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

3.2 mope local

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

$ mope local 2.11.0

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

$ mope local --unset

3.3 mope shell

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

$ mope shell 2.11.0

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

$ mope shell --unset

Note that you'll need mope'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 MOPE_VERSION variable yourself:

$ export MOPE_VERSION=2.11.0

3.4 mope versions

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

$ mope versions
* 2.10.9 (set by /Users/dragan/.mope/version)
  2.11.0

3.5 mope version

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

$ mope version
2.11.0 (set by /Users/dragan/Development/Sandbox/MonoProject/.mono-version)

3.6 mope rehash

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

$ mope rehash

3.7 mope which

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

$ mope which csharp
/Users/dragan/.mope/versions/2.11.0/bin/csharp

3.8 mope whence

Lists all Mope versions with the given command installed.

$ mope whence xsp
2.11.0

4 Development

The mope 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 (April 14, 2012)

• Initial public release.

4.2 Thanks

This project was heavily inspired by the rbenv project by Sam Stephenson.

4.3 License

mope is released under the MIT License. See LICENSE for more information.