Installing LuaJIT and Luarocks on OS X

Thanks to Homebrew, installing Lua on OS X is easy. I wanted to install the LuaJIT version as that is the one that I'm likely to be using in the future. It was just a matter of:

    $ brew install luajit

I also wanted to install the Luarocks package manager. My first attempt failed.

Then I found the very helpful instructions at Mesca's Homebrew-Luarocks page. 

Sadly, it is no longer available via Homebrew. I need to find a new method to install Luarocks to use with Luajit

Installing gtk3 Ruby Gem on OS X Yosemite

As I found installing the gtk3 Ruby Gem on OS X Yosemite is a little fiddly, I thought I'd make a note of how to do it for next time so that I don't need to spend time searching the internet to found out how.

First, you need to install X-windows. That's pretty straightforward simply click on the X.11 icon in the Others collection in LaunchPad and follow the instructions.

Second, you need to install gtk+3 itself. Using HomeBrew that's straightforward:

    brew install gtk+3

Then the tricky bit. You need to help gem find the correct libffi library. I found  out how to do it thanks to the Ruby-Gnome team:

   sudo PKG_CONFIG_PATH=/usr/local/opt/libffi/lib/pkgconfig gem install gtk3