https://github.com/freemasen/rbr-wasmer

https://github.com/freemasen/rbr-plugins

• Bytecode
• Needs VM

# #![allow(unused_variables)]
#fn main() {
#[no_mangle]
pub fn double(n: u32) -> u32 {
    n * 2
}
#}

(module
  (type $t0 (func (param i32) (result i32)))
  (func $double (export "double") (type $t0) (param $p0 i32) (result i32)
    (i32.shl
      (local.get $p0)
      (i32.const 1)))
  (table $T0 1 1 funcref)
  (memory $memory (export "memory") 16)
  (global $g0 (mut i32) (i32.const 1048576))
  (global $__data_end (export "__data_end") i32 (i32.const 1048576))
  (global $__heap_base (export "__heap_base") i32 (i32.const 1048576)))

• The simplest VM to use right now

• Rust (obviously)
• The wasm32-unknown-unknown target
  • rustup target add wasm32-unknown-unknown
• Cmake
  • MacOS
    • brew install cmake
    • ports install cmake
  • Debian/Ubuntu
    • apt-get install cmake
  • FreeBSD
    • pkg install cmake
  • Windows
    • choco install cmake
    • (cmake.org/download)[https://cmake.org/download/]

• Only knows numbers

• Remember WASM Only Knows Numbers
  • How could we pass/return a String?

# #![allow(unused_variables)]
#fn main() {
//                0,1,2,3,4, 5 , 6 , 7 , 8 , 9 , 10
let memory = vec![0,0,0,0,0,100,111,117,98 ,108,101];
//                ®,0,0.0.0, d , o , u , b , l , e
let wi_len = vec![0,0,0,0,6,100,111,117,98 ,108,101];
//                 [ 6u32 ], d , o , u , b , l , e
let double = vec![0,0,0,0,12,100,111,117,98 ,108,101,100,111,117,98 ,108,101]
//                [ 12u32 ] , d , o , u , b , l , e , d , o , u , b , l , e
#}

with a little unsafe

• Import a function from the host
  • First Arg always Context

• Attribute Macro
• TokenStreams to TokenStreams

• What if we wanted to work with even more complicated data?
• Could we use a binary serialization format?
  • Bincode
  • cbor
  • msg-pack