The interpreter was the easiest; it took me a morning to get that working albeit without support for nested parens. After that, I decided to write a text to Brainfuck converter, which (not surprisingly) turns text into executable Brainfuck code. Maybe if I get bored again, I could write a module to output the equivalent Perl or C code given some Brainfuck code.

This was my first real project using object oriented Perl. In all honesty, I like that Perl’s object system allows for many different types of objects (objects can be scalars, arrays, or hashes) and how flexible that is. Unfortunately, I didn’t get to exploit that flexibility in my code. It’s still cool though.

What I wrote is 2 Perl modules that make up the linked list that store data generated by Brainfuck code, a Perl module that interprets and runs the code, and a Perl module that translates text to executable Brainfuck code. I know I could have used a pre-built linked list, but I thought it was more fun to write my own.

The biggest challenge was definitely writing the translation code. I could’ve done it the easy way, and just output x amount of pluses for the character code of each letter, but I decided that was the lamest way to write Brainfuck. Instead, I looped through each character in the phrase, and added some nodes in my Brainfuck code that corresponded to the tens place of each character code. Then, when outputting a character, my Brainfuck code would change the data pointer to the node that was set to the tens place of the character code of the desired character, and increment or decrement it to the proper value.

A more ideal way to do it (to generate cleaner Brainfuck, at least) is to set each of those prep nodes to the nearest multiple of 20 for each character code, and then use whichever node is closest to the desired value. Maybe if I feel like doing more with this, then I’ll add that feature (probably not).

In addition to writing all this, I also made a GitHub account. My GitHub has all the above code, so you can clone the repo if you want to see what the code looks like (it’s actually really easy to read Perl).

This whole idea came from an idea on CSH. A guy here decided to publish a “Hello World of the Week” article in our newsletter, and to combat him I wrote a Brainfuck version of Hello World. This contest grew, and other people joined (albeit humorously) with such contributions as a boot loader that printed out Hello World, Hello World in White Space, and Hello World in Microsoft Word. My contribution (also in my git repo) generated valid Brainfuck code for the phrase Hello World, and then ran it through my interpreter (aka Hello World in 425ish lines).

The biggest issue (so far) was file uploads. So here’s a quick tutorial on how to do file uploads with perl, with mason.

In index.html (or wherever your form HTML code lives):

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<form method="post" action="upload.mas" enctype="multipart/form-data">
  <input type="file" name="file_name" /><br />
  <input type="submit" value="Submit" />
</form>

In upload.mas:

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<%init>
    use Apache2::Upload;
 
    # $r is an Apache2::RequestRec, not an Apache2::Request like some places say it is
    my $req = Apache2::Request->new($r);
 
    # file_name refers to the form name you had in your HTML
    my $upload = $req->upload('file_name');
 
    my $fh = $upload->fh;
    open OUTFILE, ">$where_ever_you_wanna_save_the)file";
 
    binmode $fh;
    binmode OUTFILE;
 
    print OUTFILE $line foreach my $line (<$fh>);
    close OUTFILE;
    close $fh;
</%init>

In your httpd.conf:

APREQ2_READLIMIT 2G # Sets the max size of your user's uploads to 2GB

I intentionally skipped over error handling code and all of the httpd.conf config for the sake of brevity (I did say brief tutorial). Since I need to allow for larger file sizes than Apache does by default (64MB), I spent quite some time looking for that Apache directive.

Hopefully this saves someone some time.

I also got a bunch of the abstraction for my CS project done today. But that wasn’t that much code. Oh well.

Also, in the middle of this post, got roped into helping fix our Xen management interface. And by help, I meant I installed Ubuntu server (ugh) on a machine and installed openssh. Woo.

For my CS project, me and a partner have to write a game playing framework, and then a bunch of pluggable games for the framework. It’s a lot easier than it sounds, as they’re all little command line games like take away, kayles, or connect 3. It’s still pretty cool though. It’s weird to be working with objects again after mostly programming in C this summer. But yeah, so the project is coming along. It’s nice, because right now I only really have to write the abstract framework while my partner writes the game parts that inherit from my framework. Also I have to fix the old game. But whatever, that should be easy.

My Omegle app is coming along slowly. Trying to figure out perl GTK+ while figuring out perl OO while figuring out the ill-documented WWW::Omegle perl module. Fun times. Actually, typing this made me realize I should OO it up a little more. Gonna go back to work after this post.

I definitely need to finish up the slides for the presentations I’m gonna give CSH. I’m gonna publish them on here too, under a new “Presentations” section. It should look pretty hot.

Anyway, I should go back to being productive, cause I haven’t done as much as I wanted.