Module vm 

A virtual machine and its runtime values.

Examples

Embedding Scheme scripts in Rust with a custom virtual machine

First, prepare a Scheme script named src/hello.scm.

(import (scheme base))

(write-string "Hello, world!\n")

Then, add a build script at build.rs to build the Scheme source file into bytecode.

use stak_build::{build_r7rs, BuildError};

fn main() -> Result<(), BuildError> {
    build_r7rs()
}

Finally, you can include the Scheme script into a Rust program using include_module macro and run the script.

use core::error::Error;
use stak::{
    device::StdioDevice,
    file::VoidFileSystem,
    include_module,
    process_context::VoidProcessContext,
    module::Module,
    r7rs::{SmallError, SmallPrimitiveSet},
    time::VoidClock,
    vm::Vm,
};

const HEAP_SIZE: usize = 1 << 16;

fn main() -> Result<(), Box<dyn Error>> {
    // Include and run a Scheme script in the bytecode format built by the build script above.
    run(&include_module!("hello.scm").bytecode())?;

    Ok(())
}

fn run(bytecode: &[u8]) -> Result<(), SmallError> {
    // Prepare a heap memory of a virtual machine.
    let mut heap = [Default::default(); HEAP_SIZE];
    // Create a virtual machine with its heap memory primitive procedures.
    let mut vm = Vm::new(
        &mut heap,
        SmallPrimitiveSet::new(
            // Attach standard input, output, and error of this process to a virtual machine.
            StdioDevice::new(),
            // Use void system interfaces for security because we don't need them for this example.
            VoidFileSystem::new(),
            VoidProcessContext::new(),
            VoidClock::new(),
        ),
    )?;

    // Initialize a virtual machine with bytecode.
    vm.initialize(bytecode.iter().copied())?;
    // Run bytecode on a virtual machine.
    vm.run()
}

Structs

Cons

A cons.

Memory

A memory on a virtual machine.

Number

A number.

Value

A value.

Vm

A virtual machine.

Enums

Error

An error of a virtual machine.

StackSlot

A tag of a stack slot.

Type

A type in Scheme.

Traits

Exception

An exception.

PrimitiveSet

A primitive set.

Profiler

A profiler.

Type Aliases

Tag

A tag.