One of the things I love the most about programming is that sometimes you feel like you're taking a step forward when you're taking a step back... and sometimes you feel like you're taking a step back when you take a step forward.

Or maybe that's just me. XD

Over the summer I was recruited to be a supplement instructor for a data structures course. As a result of that I was asked (separately by the professor) to be a grader for the course. Because of pay limitations I've mostly been grading homework project assignments. In any case, it's a great job to get my foot into the department and get recognized.

Over the course of the semester I've had this one person, OSX, named after their operating system of choice, who has been giving me awkward submissions. On the first assignment they asked the professor for extra time for some reason or the other, and that's perfectly fine.

So I finally receive OSX's submission, and it's a .py file as per course of the course. So I pop up a terminal in the working directory and type "python OSX_hw1.py". Get some error spit out about the file not being the right encoding. I know that I can tell python to read it in a different encoding, so I open it up in a text editor. To my surprise it's totally not a text file, but rather a .zip file!

I've seen weirder things done before, so no big deal. I rename the file extension, and open it up to extract the files when I see that there's no python files. "Okay, what's goin on here OSX..." I think to myself.

Poking around in the files it appears to be some sort of meta-data. To what, I had no clue, but what I did find was picture files containing what appeared to be some auto-generated screenshots of incomplete code. Since I'm one to give people the benefit of doubt even when they've long exhausted other peoples', I thought that it must be some fluke, and emailed OSX along with the professor detailing my issue.

I got back a rather standard reply, one of which was so un-notable I could not remember it if my life depended on it. However, that also meant I didn't have to worry about that anymore. Which when you're juggling 50 bazillion things is quite a relief. Tragically, this relief was short lived with the introduction of assignment 2.

Assignment 2 comes around, and I get the same type of submission from OSX. At this time I also notice that all their submissions are *very* close to the due time of 11:59pm (which I don't care about as long as it's in before people start waking up the next morning). I email OSX and the professor again, and receive a similar response. I also get an email from OSX worried about points being deducted. I reply, "No issue. You know what's wrong. Go and submit the right file on $CentralGradingCenter. Just submit over your old assignment".

To my frustration OSX claimed to not know how to do this. I write up a quick response explaining the process, and email it. In response OSX then asks if I can show them if they comes to my supplemental lesson. I tell OSX that if they are the only person, sure, otherwise no because it would not be a fair use of time to the other students.

OSX ends up showing up before anyone else, so I guide them through the process. It's pretty easy, so I'm surprised that they were having issues. Another person then shows up, so I go through relevant material and ask them if they have any questions about recent material in class. That said, afterwards OSX was being somewhat awkward and pushy trying to shake my hand a lot to the point of making me uncomfortable and telling them that there's no reason to be so formal.

Despite that chat, I still did not see a resubmission of either of those two assignments, and assignment 3 began to show it's head. Obviously, this time, as one might expect after all those conversations, I get another broken submission in the same format. Finally pissed off, I document exactly how everything looks on my end, how the file fails to run, how it's actually a zip file, etc, all with screenshots. That then gets emailed to the professor and OSX.

In response, I get an email from OSX panicking asking me how to submit it right, etc, etc. However, they also removed the professor from the CC field. In response I state that I do not know how to use whatever editor they are using, and that they should refer to the documentation in order to get a proper runnable file. I also re-CC the professor, making sure OSX's email to me is included in my reply.

OSX then shows up for one of my lessons, and since no one had shown up yet, I reiterate through what I had sent in the email. OSX's response was astonished that they could ever screw up that bad, but also admits that they had yet to install python(!!!). Obviously, the next thing that comes from my mouth is asking OSX how they write their code. Their response was that they use a website that lets them run python code.

At this point I'm honestly baffled and explain that a lot of websites like those can have limitations which might make code run differently then it should (maybe it's a simple interpreter written on JavaScript, or maybe it is real python, but how are you supposed to do file I/O?) .

After that I finally get a submission for assignment 1!

The rear ducking continues. We've built a reliable translator in the dumbest fucking way possible, it's just lovely. I simply reused the structure for feeding data to the VM assembler, an array of arrays, where there's one array of (ins [args]) per node in the parse tree.

It's nice because nodes can be solved out of order without affecting the actual sequence in which the instructions are output. And if one statement (node) equals multiple instructions, you just push multiple entries to the corresponding array, or push nothing if you need to output nothing. Easy as goblin pie.

This is enough to convert an input language to the assembly-like intermediate representation we use for the virtual machine. So then there's doing it backwards: walk the same array of arrays, and map those virtual instructions to a physical architechture. I guess I could do the encoding to native binary myself, it'd certainly be interesting to try, but I'm burnt-out already so I'll just use fasm for now.

Initial test: wrote a test program in my own stupid language, ran the translator, dump output to file, assemble that with fasm, run with r2 -d.

Crashes? No.
Runs fine? Yes and no.

For fuck's sake, I don't have syscalls. Mainly because the VM doesn't have an operating system, lmao. I was testing virtual programs by just freezing state, terminating, then dumping the fucking registers and stack to the console, we have no I/O to speak of. Not even a real 'exit', VM handles that by reading a return value every step like a mentally damaged son of a bitch.

So anyway, I manually paste the linux mambo, you know:

mov rax,60
mov rdi,0
syscall

And NOW our program can end execution without crashing.
Okay then, so does the test code work correctly?

** DRUM ROLL **

Yes.

Ladies and gentlemen, mother fucking PESO is now a compiled language, and going forward I will be expectantly receiving your marriage proposals for reviewing. Oh, but not so fast, we still need a frontend...

Well, we'll handle that in the next few days. I'm just glad to be *nearly* finished with this fucking compiler, I want nothing to do with anything else ever, but we know that's not going to happen, so Lord please end my pain.

No sponsor as this rant has been paid for by tax evasion.