Feature: load program from disk about mac

[felixangell]

Do you mean like hot swapping the code? I'm confused

[yorickdewid]

To load the program from a (encoded) file so that the vm really 'runs' the code instead of the hardcoding a predefined structure. Much like interpreter vm's such as CPython do. Its really just an extention to your idea :)

[felixangell]

Oh wait sorry, I thought this was for Alloy and not mac so I was really confused. Yeah you could do file IO, it should be relatively easy. I would do it, but I don't want to deviate too much from the article that this repository is for.

Or even better, you could write an assembler that translates something like

psh 5
psh 5
add
hlt

To whatever the instructions are, and then you feed that into the VM, bam you got yourself a little assembly language for your custom vm! :) I may consider implementing something like this for the advanced version of Mac; but for now it serves for a guide/tutorial as opposed to a virtual machine for something more serious.

[yorickdewid]

Say the thing, read the article (excellent by the way 👍 ) and I kind of was expecting you'd want to stick to the blog post. Anyway, I'm planning on doing something myself later this year including a tokenizer and the parse/AST story. Something Python based, but with a smaller footprint. Petty possible some of the Alloy concepts will be present and ofcourse the VM

[felixangell]

Thanks! 11/10 would write another article again, Matz -- the guy who created Ruby -- tweeted my article!!!!!!!!!!!!!!!!! 😲 And yeah, sounds awesome, virtual machines are great. They're what got me into more lower level concepts of computers like compilers, etc. I'll check it out when it's up :)

For now, I'm going to close the issue; but it doesn't mean I won't implement this later on :)

[felixangell]

Might do this later today on another branch since I'm kinda bored :)

[yorickdewid]

I'll check it out then 👍

[felixangell]

@yorickdewid 😀 I'll be back in around 2 hours and I'll probably work on it then :)

[felixangell]

@yorickdewid Done :) Mac improved now reads a binary file from the disk.

[yorickdewid]

Seems to be working, nice. Though it looks like you don't allocate enough for the instructions array.
Anyway you should add some cleanup procedures to free the blocks and close the descriptor.

Looks pretty good, next step is to generate these .mac files based on user input? :)

[felixangell]

@yorickdewid It allocates more space when necessary, and the instructions buffer is increased exponentially. And good catch on the cleanup, forgot about that. Oh, found another bug too.

And what you're suggesting is an assembler, it takes an assembly file and creates the .mac files. These are still quite simple, but I'll leave that as an exercise for the reader ;) It shouldn't be too tricky, and you can even do some more fancy stuff like checking if the actual logic of the assembly is correct etc.