Struct mlua::Thread

source ·
pub struct Thread<'lua>(_);
Expand description

Handle to an internal Lua thread (or coroutine).


Resumes execution of this thread.

Equivalent to coroutine.resume.

Passes args as arguments to the thread. If the coroutine has called coroutine.yield, it will return these arguments. Otherwise, the coroutine wasn’t yet started, so the arguments are passed to its main function.

If the thread is no longer in Active state (meaning it has finished execution or encountered an error), this will return Err(CoroutineInactive), otherwise will return Ok as follows:

If the thread calls coroutine.yield, returns the values passed to yield. If the thread returns values from its main function, returns those.

let thread: Thread = lua.load(r#"
        assert(arg == 42)
        local yieldarg = coroutine.yield(123)
        assert(yieldarg == 43)
        return 987

assert_eq!(thread.resume::<_, u32>(42)?, 123);
assert_eq!(thread.resume::<_, u32>(43)?, 987);

// The coroutine has now returned, so `resume` will fail
match thread.resume::<_, u32>(()) {
    Err(Error::CoroutineInactive) => {},
    unexpected => panic!("unexpected result {:?}", unexpected),

Gets the status of the thread.

Resets a thread

In Lua 5.4: cleans its call stack and closes all pending to-be-closed variables. Returns a error in case of either the original error that stopped the thread or errors in closing methods.

In LuaJIT and Luau: resets to the initial state of a newly created Lua thread. Lua threads in arbitrary states (like yielded or errored) can be reset properly.

Sets a Lua function for the thread afterwards.

Requires feature = "lua54" OR feature = "luajit,vendored" OR feature = "luau"

Available on crate feature async only.

Converts Thread to an AsyncThread which implements Future and Stream traits.

args are passed as arguments to the thread function for first call. The object calls resume() while polling and also allows to run rust futures to completion using an executor.

Using AsyncThread as a Stream allows to iterate through coroutine.yield() values whereas Future version discards that values and poll until the final one (returned from the thread function).

Requires feature = "async"

use futures::stream::TryStreamExt;
let thread: Thread = lua.load(r#"
    coroutine.create(function (sum)
        for i = 1,10 do
            sum = sum + i
        return sum

let mut stream = thread.into_async::<_, i64>(1);
let mut sum = 0;
while let Some(n) = stream.try_next().await? {
    sum += n;

assert_eq!(sum, 286);

Trait Implementations

Returns a copy of the value. Read more
Performs copy-assignment from source. Read more
Formats the value using the given formatter. Read more
Performs the conversion.
This method tests for self and other values to be equal, and is used by ==. Read more
This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason. Read more
Performs the conversion.

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
Uses borrowed data to replace owned data, usually by cloning. Read more
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.