Struct magnus::value::Opaque

pub struct Opaque<T>(/* private fields */);

A wrapper to make a Ruby type Send + Sync.

Ruby types are not Send or Sync as they provide a way to call Ruby’s APIs, which it is not safe to do from a non-Ruby thread.

Ruby types are safe to send between Ruby threads, but Rust’s trait system currently can not model this detail.

To resolve this, the Opaque type makes a Ruby type Send + Sync by removing the ability to do anything with it, making it impossible to call Ruby’s API on non-Ruby threads.

An Opaque<T> can be unwrapped to T with Ruby::get_inner, as it is only possible to instantiate a Ruby on a Ruby thread.

Examples

use magnus::{rb_assert, value::Opaque, Ruby};

let ruby = Ruby::get().unwrap();
let opaque_str = Opaque::from(ruby.str_new("example"));

// send to another Ruby thread

let ruby = Ruby::get().unwrap(); // errors on non-Ruby thread
let str = ruby.get_inner(opaque_str);
rb_assert!(ruby, r#"str == "example""#, str);

Trait Implementations

impl<T: Clone> Clone for Opaque<T>

fn clone(&self) -> Opaque<T>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T> From<T> for Opaque<T>

where T: ReprValue,

fn from(val: T) -> Self

Converts to this type from the input type.

impl<T> InnerRef for Opaque<T>

where T: ReprValue,

type Value = T

The specific Ruby value type.

fn get_inner_ref_with<'a>(&'a self, _: &Ruby) -> &'a Self::Value

Get a reference to the inner value from self.

impl<T> InnerValue for Opaque<T>

where T: ReprValue,

type Value = T

The specific Ruby value type.

fn get_inner_with(self, _: &Ruby) -> Self::Value

Get the inner value from self.

impl<T> IntoValue for Opaque<T>

where T: IntoValue,

fn into_value_with(self, handle: &Ruby) -> Value

Convert self into Value.

fn into_value(self) -> Value

Convert self into Value.

unsafe fn into_value_unchecked(self) -> Value

Convert self into Value.

impl<T: Copy> Copy for Opaque<T>

impl<T> Locate for Opaque<T>

where T: ReprValue,

impl<T> Mark for Opaque<T>

where T: ReprValue,

impl<T: ReprValue> Send for Opaque<T>

impl<T: ReprValue> Sync for Opaque<T>