Struct actix_lua::dev::rlua::prelude::Lua

pub struct Lua { /* fields omitted */ }

Top level Lua struct which holds the Lua state itself.

Methods

impl Lua

pub fn new() -> Lua

Creates a new Lua state and loads standard library without the debug library.

pub unsafe fn new_with_debug() -> Lua

Creates a new Lua state and loads the standard library including the debug library.

The debug library is very unsound, loading it and using it breaks all the guarantees of rlua.

pub fn load<S>(&self, source: &S, name: Option<&str>) -> Result<Function, Error> where     S: AsRef<[u8]> + ?Sized,

Loads a chunk of Lua code and returns it as a function.

The source can be named by setting the name parameter. This is generally recommended as it results in better error traces.

Equivalent to Lua's load function.

pub fn exec<'lua, S, R>(     &'lua self,     source: &S,     name: Option<&str> ) -> Result<R, Error> where     R: FromLuaMulti<'lua> + FromLuaMulti<'lua>,     S: AsRef<[u8]> + ?Sized,

Execute a chunk of Lua code.

This is equivalent to simply loading the source with load and then calling the resulting function with no arguments.

Returns the values returned by the chunk.

pub fn eval<'lua, S, R>(     &'lua self,     source: &S,     name: Option<&str> ) -> Result<R, Error> where     R: FromLuaMulti<'lua>,     S: AsRef<[u8]> + ?Sized,

Evaluate the given expression or chunk inside this Lua state.

If source is an expression, returns the value it evaluates to. Otherwise, returns the values returned by the chunk (if any).

pub fn create_string<S>(&self, s: &S) -> Result<String, Error> where     S: AsRef<[u8]> + ?Sized,

Create and return an interned Lua string. Lua strings can be arbitrary u8 data including embedded nulls, so in addition to &str and &String, you can also pass plain &[u8] here.

pub fn create_table(&self) -> Result<Table, Error>

Creates and returns a new table.

pub fn create_table_from<'lua, K, V, I>(     &'lua self,     cont: I ) -> Result<Table<'lua>, Error> where     I: IntoIterator<Item = (K, V)>,     K: ToLua<'lua>,     V: ToLua<'lua>,

Creates a table and fills it with values from an iterator.

pub fn create_sequence_from<'lua, T, I>(     &'lua self,     cont: I ) -> Result<Table<'lua>, Error> where     I: IntoIterator<Item = T>,     T: ToLua<'lua>,

Creates a table from an iterator of values, using 1.. as the keys.

pub fn create_function<'callback, A, R, F>(     &'lua self,     func: F ) -> Result<Function<'lua>, Error> where     A: FromLuaMulti<'callback>,     F: 'static + Send + Fn(&'callback Lua, A) -> Result<R, Error>,     R: ToLuaMulti<'callback>,

Wraps a Rust function or closure, creating a callable Lua function handle to it.

The function's return value is always a Result: If the function returns Err, the error is raised as a Lua error, which can be caught using (x)pcall or bubble up to the Rust code that invoked the Lua code. This allows using the ? operator to propagate errors through intermediate Lua code.

If the function returns Ok, the contained value will be converted to one or more Lua values. For details on Rust-to-Lua conversions, refer to the ToLua and ToLuaMulti traits.

Examples

Create a function which prints its argument:

let lua = Lua::new();

let greet = lua.create_function(|_, name: String| {
    println!("Hello, {}!", name);
    Ok(())
});

Use tuples to accept multiple arguments:

let lua = Lua::new();

let print_person = lua.create_function(|_, (name, age): (String, u8)| {
    println!("{} is {} years old!", name, age);
    Ok(())
});

pub fn create_function_mut<'callback, A, R, F>(     &'lua self,     func: F ) -> Result<Function<'lua>, Error> where     A: FromLuaMulti<'callback>,     F: 'static + Send + FnMut(&'callback Lua, A) -> Result<R, Error>,     R: ToLuaMulti<'callback>,

Wraps a Rust mutable closure, creating a callable Lua function handle to it.

This is a version of create_function that accepts a FnMut argument. Refer to create_function for more information about the implementation.

pub fn create_thread(     &'lua self,     func: Function<'lua> ) -> Result<Thread<'lua>, Error>

Wraps a Lua function into a new thread (or coroutine).

Equivalent to coroutine.create.

pub fn create_userdata<T>(&self, data: T) -> Result<AnyUserData, Error> where     T: 'static + Send + UserData,

Create a Lua userdata object from a custom userdata type.

pub fn globals(&self) -> Table

Returns a handle to the global environment.

pub fn scope<'scope, 'lua, F, R>(&'lua self, f: F) -> R where     'lua: 'scope,     F: FnOnce(&Scope<'scope>) -> R,

Calls the given function with a Scope parameter, giving the function the ability to create userdata and callbacks from rust types that are !Send or non-'static.

The lifetime of any function or userdata created through Scope lasts only until the completion of this method call, on completion all such created values are automatically dropped and Lua references to them are invalidated. If a script accesses a value created through Scope outside of this method, a Lua error will result. Since we can ensure the lifetime of values created through Scope, and we know that Lua cannot be sent to another thread while Scope is live, it is safe to allow !Send datatypes and whose lifetimes only outlive the scope lifetime.

Handles that Lua::scope produces have a 'lua lifetime of the scope parameter, to prevent the handles from escaping the callback. However, this is not the only way for values to escape the callback, as they can be smuggled through Lua itself. This is safe to do, but not very useful, because after the scope is dropped, all references to scoped values, whether in Lua or in rust, are invalidated. Function types will error when called, and AnyUserData types will be typeless.

pub fn coerce_string(&'lua self, v: Value<'lua>) -> Option<String<'lua>>

Attempts to coerce a Lua value into a String in a manner consistent with Lua's internal behavior.

To succeed, the value must be a string (in which case this is a no-op), an integer, or a number.

pub fn coerce_integer(&self, v: Value) -> Option<i64>

Attempts to coerce a Lua value into an integer in a manner consistent with Lua's internal behavior.

To succeed, the value must be an integer, a floating point number that has an exact representation as an integer, or a string that can be converted to an integer. Refer to the Lua manual for details.

pub fn coerce_number(&self, v: Value) -> Option<f64>

Attempts to coerce a Lua value into a Number in a manner consistent with Lua's internal behavior.

To succeed, the value must be a number or a string that can be converted to a number. Refer to the Lua manual for details.

pub fn pack<'lua, T>(&'lua self, t: T) -> Result<Value<'lua>, Error> where     T: ToLua<'lua>,

Converts a value that implements ToLua into a Value instance.

pub fn unpack<'lua, T>(&'lua self, value: Value<'lua>) -> Result<T, Error> where     T: FromLua<'lua>,

Converts a Value instance into a value that implements FromLua.

pub fn pack_multi<'lua, T>(&'lua self, t: T) -> Result<MultiValue<'lua>, Error> where     T: ToLuaMulti<'lua>,

Converts a value that implements ToLuaMulti into a MultiValue instance.

pub fn unpack_multi<'lua, T>(     &'lua self,     value: MultiValue<'lua> ) -> Result<T, Error> where     T: FromLuaMulti<'lua>,

Converts a MultiValue instance into a value that implements FromLuaMulti.

pub fn set_named_registry_value<'lua, T>(     &'lua self,     name: &str,     t: T ) -> Result<(), Error> where     T: ToLua<'lua>,

Set a value in the Lua registry based on a string name.

This value will be available to rust from all Lua instances which share the same main state.

pub fn named_registry_value<'lua, T>(&'lua self, name: &str) -> Result<T, Error> where     T: FromLua<'lua>,

Get a value from the Lua registry based on a string name.

Any Lua instance which shares the underlying main state may call this method to get a value previously set by set_named_registry_value.

pub fn unset_named_registry_value(&'lua self, name: &str) -> Result<(), Error>

Removes a named value in the Lua registry.

Equivalent to calling set_named_registry_value with a value of Nil.

pub fn create_registry_value<'lua, T>(     &'lua self,     t: T ) -> Result<RegistryKey, Error> where     T: ToLua<'lua>,

Place a value in the Lua registry with an auto-generated key.

This value will be available to rust from all Lua instances which share the same main state.

pub fn registry_value<'lua, T>(     &'lua self,     key: &RegistryKey ) -> Result<T, Error> where     T: FromLua<'lua>,

Get a value from the Lua registry by its RegistryKey

Any Lua instance which shares the underlying main state may call this method to get a value previously placed by create_registry_value.

pub fn remove_registry_value(&self, key: RegistryKey) -> Result<(), Error>

Removes a value from the Lua registry.

You may call this function to manually remove a value placed in the registry with create_registry_value. In addition to manual RegistryKey removal, you can also call expire_registry_values to automatically remove values from the registry whose RegistryKeys have been dropped.

pub fn owns_registry_value(&self, key: &RegistryKey) -> bool

Returns true if the given RegistryKey was created by a Lua which shares the underlying main state with this Lua instance.

Other than this, methods that accept a RegistryKey will return Error::MismatchedRegistryKey if passed a RegistryKey that was not created with a matching Lua state.

pub fn expire_registry_values(&self)

Remove any registry values whose RegistryKeys have all been dropped.

Unlike normal handle values, RegistryKeys do not automatically remove themselves on Drop, but you can call this method to remove any unreachable registry values not manually removed by Lua::remove_registry_value.

Trait Implementations

impl Drop for Lua

fn drop(&mut self)

Executes the destructor for this type.

impl Send for Lua