the "transmute lifetimes" solution

This commit is contained in:
Quaternions 2024-09-20 13:51:17 -07:00
parent acfdc1bd5e
commit aa0bee9f69
3 changed files with 17 additions and 18 deletions

View File

@ -10,16 +10,17 @@ pub fn class_is_a(class:&str,superclass:&str)->bool{
)
}
#[repr(transparent)]
pub struct Context{
pub(crate)dom:WeakDom,
}
impl Context{
pub fn new(dom:WeakDom)->Context{
pub const fn new(dom:WeakDom)->Context{
Context{dom}
}
pub fn into_inner(self)->WeakDom{
self.dom
pub fn from_mut(dom:&mut WeakDom)->&mut Context{
unsafe{&mut *(dom as *mut WeakDom as *mut Context)}
}
/// Creates an iterator over all items of a particular class.
pub fn superclass_iter<'a>(&'a self,superclass:&'a str)->impl Iterator<Item=Ref>+'a{

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@ -26,7 +26,8 @@ impl Instance{
// LMAO look at this function!
fn dom<T>(lua:&mlua::Lua,mut f:impl FnMut(&mut WeakDom)->mlua::Result<T>)->mlua::Result<T>{
f(&mut *lua.app_data_mut::<WeakDom>().ok_or(mlua::Error::runtime("DataModel missing"))?)
let mut dom=lua.app_data_mut::<&'static mut WeakDom>().ok_or(mlua::Error::runtime("DataModel missing"))?;
f(&mut *dom)
}
fn coerce_float(value:&mlua::Value)->Option<f32>{

View File

@ -76,19 +76,16 @@ impl Runner{
init(&runner.lua)?;
Ok(runner)
}
pub fn run_script(&self,script:crate::script::Script,context:Context)->(Context,Result<(),Error>){
let yoink=script.name_source(&context);
self.lua.set_app_data(context.dom);
let r=(||{
pub fn run_script(&self,script:crate::script::Script,context:&mut Context)->Result<(),Error>{
let yoink=script.name_source(context);
//this makes set_app_data shut up about the lifetime
self.lua.set_app_data::<&'static mut rbx_dom_weak::WeakDom>(unsafe{core::mem::transmute(&mut context.dom)});
let (name,source)=yoink.map_err(Error::Script)?;
self.lua.globals().set("script",super::instance::Instance::from(script)).map_err(Error::Lua)?;
self.lua.load(source)
.set_name(name)
.exec().map_err(Error::Lua)?;
self.lua.remove_app_data::<&'static mut rbx_dom_weak::WeakDom>();
Ok(())
})();
let dom=self.lua.remove_app_data()
.expect("Fatal: Lua lost the dom");
(Context::new(dom),r)
}
}