Struct Memoized

pub struct Memoized {
    pub to_value: Arc<dyn Fn(&Lua) -> Result<Value> + Send + Sync>,
}

Memoized is a helper type that allows native Rust types to be captured in memoization caches. Unfortunately, we cannot automatically make that work for all UserData that are exported to lua, but we can make it simple for a type to opt-in to that behavior.

When you impl UserData for your type, you can call Memoized::impl_memoize(methods) from your add_methods impl. That will add a metamethod to your UserData type that will clone your value and wrap it into a Memoized wrapper.

Since Clone is used, it is recommended that you use an Arc inside your type to avoid making large or expensive clones.

Fields

to_value: Arc<dyn Fn(&Lua) -> Result<Value> + Send + Sync>

Implementations

impl Memoized

pub fn impl_memoize<T, M>(methods: &mut M)

where T: UserData + Send + Sync + Clone + 'static, M: UserDataMethods<T>,

Call this from your UserData::add_methods implementation to enable memoization for your UserData type

Trait Implementations

impl Clone for Memoized

fn clone(&self) -> Memoized

Returns a copy of the value.

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

Performs copy-assignment from source.

impl FromLua for Memoized

where Self: 'static + Clone,

fn from_lua(value: Value, _: &Lua) -> Result<Self>

Performs the conversion.

impl PartialEq for Memoized

fn eq(&self, other: &Self) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl UserData for Memoized

fn add_fields<F>(fields: &mut F)

where F: UserDataFields<Self>,

Adds custom fields specific to this userdata.

fn add_methods<M>(methods: &mut M)

where M: UserDataMethods<Self>,

Adds custom methods and operators specific to this userdata.

fn register(registry: &mut UserDataRegistry<Self>)

Registers this type for use in Lua.