What is this?

A derive macro for (de)serializing your own enums into bytecode, mainly for the purpose of building VMs

Why?

Converting enums with hundreds of variants into bytecode and back is not fun. This crate aims to automate this task with a fairly opinionated layout that makes it easy to focus on your VM's instructions rather than how it's laid out in memory.

Usage

// The instructions our VM can handle
pub enum Instruction {
// Unit variants
Nop,

// Tuple variants
Jmp(usize),

// Struct variants
Add {
a: usize,
b: usize,
store_in: usize,
},

//Supports most `std` types
Etc(u8, i16, f32, usize, Option<char>, bool),

// Variable-size items
PushString(String),
PushMany(Vec<u32>),

// Arrays and tuples
Foo( ([u8; 3], [u32; 4]) ),

// Rust type system allows for powerful composition
DoFiveTimes(Box<Instruction>)
}

Automatic resizing

By default, the enum variant is encoded as a u8. However, if your enum grows to >256 items the Serialize macro will instead use a u16. Be careful as this may invalidate any previously-compiled bytecode files!