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For some reason, the Gentoo install of erlang put the man pages into man sections that ended in “erl”. For example, instead a directory named man3 for the 3rd man page section, it’s man3erl.

I wrote a quick alias erlman that only searches these erlang man page sections.

~/.bashrc

My journey into the world of Erlang is progressing nicely. I’m really excited by the possibilities the language offers.

I wanted to get more perspective on functional programming by learning another functional language as well. Since my forays into LISP over the years never amounted to much, I decided to try out Haskell. I’ve been concerned about the buzz surrounding Erlang — buzz always seems to mask why something really is good or useful, because some are clamoring that it’s good and useful for everything.

So, I ordered a copy of “Haskell: the Craft of Functional Programming” — I mean heck, how do you spend your Fridays?

On pages 29-30 of “Programming Erlang” by Joe Armstrong, the author goes over character strings. Erlang uses Latin-1 as it’s character set. At first, Terminal.app wasn’t showing the non-US / ASCII characters.

There’s a two-step process to solve this:

1. Terminal->Window Settings…->Display->”Character Set Encoding” set to “Western (ISO Latin 1)”
2. Set the environment variable LC_ALL to “en_US” before you run erl. Also, see the next paragraph for explanations.

The above steps are for U.S. English — something similar is available for most locales, but I don’t know the specifics. Of note, is the 2nd step; firstly, LC_CTYPE is the specific value to set, but LC_ALL sets LC_* to the assigned value, so one usually wants LC_ALL, unless you have a very unique locale configuration. Secondly, I’m using Gentoo Prefix Portage environment on OSX, so while I feel that these directions are applicable to most OSX installs, my setup is slightly different, so your mileage may vary. Thirdly, for those that need UTF-8, they can set LC_ALL to “en_US.UTF-8″, and then they only have to toggle Terminal.app’s character set encoding. Why en_US.UTF-8 works, I do not know — Latin 1 is not a subset of UTF-8, so I’ll leave that to more inquiring minds.

After you find settings that you are happy with, consider adding export LC_ALL="en_US.UTF-8" to your ~/.bash_profile if you’d like it to load with every terminal window that opens. My ~/.bash_profile sources my ~/.bashrc, because ~/.bashrc is supposed to be safe for scripts that run as your user, but non-interactively; so, ~/.bash_profile tends to get a lot of my environment look and feel code.

I’m working through the Programming Erlang book that my friend zuzu recommended to me. Forty-six pages in, and so far, so good.

I did, however, just have my mind blown. I was going through an example for creating a for-loop-like function, because erlang doesn’t have a for-loop. “Well,” I thought, “that’s interesting that you have to create your own control structures.” But then the book spelled it out straightly: you can create any control structure you want — you are not limited by the control structures that the language offers.

Result? Mind is blown.

I found this post containing a script that svn checkouts a fairly functional erlang TextMate bundle. Neat-o!

I edited the bundle to allow it to update itself, using a slightly modified form of the original script.

• Bundles->Bundle Editor->Show Bundle Editor
• Click on the menu entry text “erlang”
• Drag a new separator to the bottom of the erlang bundle menu structure
• Expand the erlang bundle menu
• Use the drop-down + to create a new command
• • Save: Nothing
  • Command(s):
    Code (bash)

    1. #!/bin/bash
    2.          
    3. if [ -z "${TM_SVN}" ]; then
    4.   echo "You must define the location of your svn client in the variable TM_SVN."
    5.   exit 1
    6. fi
    7.  
    8. echo "Changing to Bundles directory…"
    9. mkdir -p /Library/Application\ Support/TextMate/Bundles
    10. cd /Library/Application\ Support/TextMate/Bundles
    11.  
    12. if [ -d /Library/Application\ Support/TextMate/Bundles/Erlang.tmbundle ]; then
    13.   echo Erlang bundle already exists - updating…
    14.   $TM_SVN up Erlang.tmbundle
    15. else
    16.   echo Checking out Erlang bundle…
    17.   $TM_SVN –username anon –password anon co http://macromates.com/svn/Bundles/trunk/Bundles/Erlang.tmbundle/
    18. fi
    19.  
    20. echo "Reloading bundles in TextMate…"
    21. osascript -e ‘tell app "TextMate" to reload bundles’
    22.  
    23. exit 0

    as downloadble file

  • Input: None
  • Output: Show as Tool Tip

Now you can update the bundle from it’s own menu option!

I believe erlang is quickly becoming that “language I always should’ve learned” language — and all this time, I thought that language was LISP.