Struct emacs::GlobalRef

#[repr(transparent)]
pub struct GlobalRef { /* fields omitted */ }

A "global reference" that can live outside the scope of an Env. This is useful for sharing an otherwise short-lived Lisp Value across multiple invocations of Rust functions defined with defun. Examples include efficient access to interned symbols or Lisp functions, and Rust-based multi-threading.

Implementation

Cloning this struct requires an Env, so it doesn't implement Clone.

free_global_ref requires an Env. Therefore, to avoid leaking the underlying Value, free should be used to free a global reference, instead of drop. For the use case of accessing interned symbols and Lisp functions, this is a non-issue, as the values are supposed to be "static" anyway.

Methods

impl GlobalRef

pub fn call<'e, A>(&'e self, env: &'e Env, args: A) -> Result<Value> where
    A: IntoLispArgs<'e>, 

Calls this reference's value with the given arguments. An error is signaled if it is actually not a Lisp's callable.

args should be an array/slice of Value, or a tuple of different types, each implementing IntoLisp.

impl GlobalRef

pub fn new(value: Value) -> Self

Creates a new global reference for the given Value.

pub fn free(self, env: &Env) -> Result<()>

Frees this global reference.

pub fn bind<'e, 'g: 'e>(&'g self, env: &'e Env) -> Value<'e>

Returns the underlying Value, scoping its lifetime to the given Env.

pub fn clone(&self, env: &Env) -> Self

Returns a copy of this global reference.

Trait Implementations

impl Debug for GlobalRef

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<'e> FromLisp<'e> for GlobalRef

fn from_lisp(value: Value<'e>) -> Result<Self>

impl<'e> IntoLisp<'e> for &'e GlobalRef

fn into_lisp(self, env: &'e Env) -> Result<Value<'e>>

impl Send for GlobalRef

impl Sync for GlobalRef