Credit should go, where the credit is due. This script is a fork of the excellent Node Version Manager, created by Tim Casswell and Matthew Ranney. NVM is available here: https://github.com/creationix/nvm.git. Latest changes will be pulled in, whenever it is feasible. Due to different code formatting and preferences this might turn out to be too hard in the long run.

The Play! Framework (http://www.playframework.org) is a Java and/or Scala web framework, so in order for it to work you will need to have Java tooling in place. Play! 1-series is purely Java-based, but can be extended to support Scala using a dedicated module. Play! 2.x is mainly Scala based, so it is mandatory to have Scala tooling installed and in your path.

To install create a folder somewhere in your filesystem with the "pvm.sh" file inside it. I put mine in a folder called "~/utils/pvm". The normal way of using .-prefixed directories unfortunately does not work well with Play. Having a separate directory for tools won't clutter your file listings, but is conveniently available when you need to access it.

Or if you have git installed, then just clone it:

git clone git://github.com/kaiinkinen/pvm.git ~/utils/pvm

To activate pvm, you need to source it from your bash shell

. ~/utils/pvm/pvm.sh

I always add this line to my ~/.bashrc or ~/.profile file to have it automatically sources upon login.
Often I also put in a line to use a specific version of play.

To download, compile, and install the 2.0 release of play, do this:

pvm install 2.0

And then in any new shell just use the installed version:

pvm use 2.0

Or you can just run it:

pvm run 2.0

If you want to see what versions are available:

pvm ls

To restore your PATH, you can deactivate it.

pvm deactivate

To set a default Play version to be used in any new shell, use the alias 'default':

pvm alias default 2.0

To activate, you need to source bash_completion:

[[ -r $PVM_DIR/bash_completion ]] && . $PVM_DIR/bash_completion

Put the above sourcing line just below the sourcing line for PVM in your profile (.bashrc, .bash_profile).

pvm

$ pvm [tab][tab]
alias          copy-packages  help           list           run            uninstall      version        
clear-cache    deactivate     install        ls             unalias        use

pvm alias

$ pvm alias [tab][tab]
default

$ pvm alias my_alias [tab][tab]
1.2.3        1.2.4       2.0

pvm use

$ pvm use [tab][tab]
my_alias        default        1.2.3        1.2.4       2.0

pvm uninstall

$ pvm uninstall [tab][tab]
my_alias        default        1.2.3        1.2.4       2.0

If you try to install a play version and the installation fails, be sure to delete the play downloads from src (e.g. ~/utils/pvm/src/) or you might get an error when trying to reinstall them again or you might get an error like the following:

curl: (33) HTTP server doesn't seem to support byte ranges. Cannot resume.

On a unix based systems you shouldn't install pvm in a hidden directory, e.g. ~/.pvm. The play copy_directory utility function disregards directories which start with a dot, including parent directories. Running play new-module will fail with a spectacular python stack trace in this case. This applies at least to play 1.2.X, so it's safer to use some other installation directory, like ~/utils/pvm