So, you have reach the personal playpen of Robert Melton on the web, this version of the site is built in Erlang,
WebMachine, SGTE and Mochiweb. You can find the source for this site at Github.
sudo apt-get -y install build-essential m4 libncurses-dev libssh-dev unixodbc-dev libgmp3-dev libwxgtk2.8-dev libglu-dev fop xsltproc default-jdk tk8.5
Then download the tar.gz from http://www.erlang.org and simply “tar -zxvf ERLANG.tar.gz” then switch to the ERLANG directory and do a simple
./configure && make && sudo make install
and you are all set!
Currently, in my day job I am working on a project that has hit a bit of a chicken and egg research loop. This loop seems to be centered on mistake avoidance, which at that scale of this project makes sense, but our lack of ability to even guess use cases make our time investment dubious at best.
Anyway, this dove tailed well with me seeing a TED talk by Tim Harford on Trial and Error, and it set of a bit of a chain reaction reminding me of other great TED talks I had seen that touched on this topic, and related topic of risk versus reward and top down versus bottom up engineering.
Burt Rutan talks about the future of spaceflight, and in the talk is some amazing statistics on the success versus failure rates of early airplanes (30,000 attempts, a handful of successes). He calls this ‘Natural Selection’ — but it is basically just another person talking about the importance of Trial and Error.
One more for the stack, Kathryn Schulz talks about being wrong, not in abstract terms, but in personal terms. In the present tense, can you think of anything you are wrong about? It talks about the importance of stepping back from an idea, and detaching from the emotional impact of being wrong.
As much as there can be a “Best” version of “Friday” — Stephen Colbert, The Roots and Taylor Hicks comes close: http://j.mp/f1dSNW
After working some contracts using Erlang and Cassandra (Thrift) going back to PHP/MySQL has been a bit painful. The laid back client, and someone interesting work has made it bearable, but I am missing OTP profoundly.
A few months ago, I had not touched Erlang/OTP, yet it rapidly took the number one slot in my kit. It isn’t all roses, but what it brings is huge, and for me has been game changing:
I realize Erlang doesn’t have much popular support, and will probably never get mainstreamed, but at this point that just feels like a competitive advantage. The experience for me has been profound, and very different than my experience with Scala, which felt to me like more of the same (lots of other java platforms, but now with Actors!)… I didn’t feel the radical shift I felt with Erlang.
http://j.mp/hkRM3p <- absolutely cracked me up. Molestation Nursery!
*sigh* @DellHomeus new policy on shipping delays seems to be to withhold all information. Day 23 “In Production” on my L702X. #dell #sucks
If you are worried about delicious (bookmarks) going offline, switch to http://ping.fm/HXCKt — does FULL imports of tags and bookmarks
List is a bit of a disaster, but I will get it fixed up in the next couple of days.
This is an update and refactoring of my big software list for Windows. Now I will offer a couple options for a few categories, as well as add a few new categories all together. All the software unless otherwise marked is free (as in beer, sometimes as in speech).
The organization of this list will be a bit different now, as I am using external tools to help you quickly get up and running with these apps. I absolutely love Ninite, so if you want to get a jump-start, use this
(contains: Runtimes for Flash, Air, Java, Silverlight and .NET (not on apps list), Chrome, Firefox, Skype, Pidgin, Thunderbird, VLC, Audacity, Paint.NET, Picasa, OpenOffice, SumatraPDF, Microsoft Essentials, Steam, KeePass, Inkscape, uTorrent, Dropbox, Everything, TeamViewer, ImgBurn, Evernote, CCCleaner, Defraggler, Teracopy, TrueCrypt, Launchy, WinSCP, Putty and Notepad++).
Two other things, the first is you will notice I removed all the highly developer specific items, as I think these really deserve there own list. Secondly, I will be highlighting some cloud computing applications that have crept into my daily usage and replaced some of these apps.
Not In Ninite (for those looking to get up and running as quickly as possible)
Vim, Abiword, LastPass, X-Chat, WinDirState, Freemind, Dexpot, Sysinternals Suite, Virtual Clonedrive, XML Notepad, Beyond Compare($30)
Text / Idea Editors
Email Clients
Virus / Malware Protection
Web Browsers
Office Products
Compression
Password Management
Messaging
Imaging / Vector / Photography
Windows Improvements
General Utilities
Video
Audio
CD Burning / ISO Mounting
Internet Misc
Commercial Applications
Anything I am missing, leave a comment.
So, I saw and played with node.js, and one of the things that impressed me was the nice clean website.
This is just a tongue in cheek clone of the node.js website but focused on Erlang.
An example of a web server written in Erlang which responds with “Hello World” for every request. Uses misultin as the web server library.
-module(example).
-export([start/0]).
start() ->
code:add_patha(“misultin/ebin”), % web-server library
misultin:start_link([{loop, fun handle_http/1},{ip, “127.0.0.1”},{port, 8124}]),
io:format(“Server running at http://127.0.0.1:8124/~n”),
receive _ -> ok end.
handle_http(Req) ->
Req:respond(200, [{“Content-Type”, ”text/plain”}], ”Hello World”).
To run the server, put it into a file called example.erl, then compile and run it.
erlc example.erl
erl -s example
Here is an example of a simple TCP server that listens on port 8124 and echoes whatever you send it.
-module(example).
-export([start/0]).
start() ->
{ok, LSocket} = gen_tcp:listen(8124, [binary, {packet, 0}, {active, false}, {reuseaddr, true}]),
accept(LSocket).
accept(LSocket) ->
{ok, Socket} = gen_tcp:accept(LSocket),
spawn(fun() -> loop(Socket) end),
gen_tcp:send(Socket, ”Echo server\r\n”),
accept(LSocket).
loop(Socket) ->
case gen_tcp:recv(Socket, 0) of
{ok, Data} -> gen_tcp:send(Socket, Data), loop(Socket)
{error, closed} -> ok
end.
Erlang is tested and used on Linux, Macintosh, Solaris, Windows (Natively), as well as FreeBSD and OpenBSD.
Erlang’s goal is to provide an easy way to build scalable, distributed, highly concurrent, functional programs. In the “hello world” web server example above, many client connections can be handled concurrently. Erlang spawns a new Erlang process to handle each connection, these are ultra-light weight processes designed with high concurrency in mind, they are not to be confused with OS processes.
This is in contrast to today’s more common concurrency model where OS threads are employed. Thread-based networking is relatively inefficient and very difficult to use. See: this and this. Erlang will show much better memory efficiency under high-loads than systems which allocate 2mb thread stacks for each connection. Furthermore, users of Erlang are free from worries of dead-locking the process—there are no locks. Almost no function in Erlang directly performs I/O, so the process never blocks. Because nothing blocks, less-than-expert programmers are able to develop fast systems.
Erlang was designed for concurrency - having multiple tasks running simultaneously - from the ground up it was a central concern when the language was designed. Its built-in support for concurrency, which uses the process concept and message passing to get a clean separation between tasks, allows us to create fault tolerant architectures and fully utilize the multi-core hardware and distributed systems that is available to us today.
TCP handling in Erlang is easy, so by extension processing HTTP becomes straightforward. Erlang’s HTTP libraries have grown out of the authors experiences developing and working with web servers. For example, streaming data through most web frameworks is impossible. Erlang attempts to correct these problems via its process oriented nature and support for concurrency. Having the freedom to spawn a long-lived process to communicate with a single client via comet or websockets makes Erlang a delight to work with.
But what about multiple-processor concurrency? Aren’t threads necessary to scale programs to multi-core computers? Processes are necessary to scale to multi-core computers, not memory-sharing threads. The fundamentals of scalable systems are fast networking and non-blocking design—the rest is message passing. Erlang has a -smp option, which allows it to take full advantage of multiple processors with near linear scaling, and has support for distributed process built right in.
See Also:
Erlang has a detailed contribution page, but I will summarize it here. Please read the entire thing before attempting to get patches mainlined.
More detailed/specific edition:
Autodidact: A self-taught person.
We are living in a golden age for those willing to take the time to educate themselves. The resources available free of charge are astounding. There are more than you can imagine online.
Access to video lectures from many colleges and institutions available via Academic Earth and YouTube EDU. As well as some of the worlds brightest putting up short videos on TED.
Educators resources (which can make fantastic learning tools) available via Connexions and OER Commons.
Beyond all that, some of the most prestigious schools in the world are putting their content online. Including MIT, CMU, Stanford and Berkley.
If I am missing a great resource please contact me and let me know about it.