Some refactoring of the rust generated code

Always use a Pin<Rc> for the component. (This is required to support repeater
within repeater as well anyway)
Do not use the context within the binding. We can get along by simply capturing
a weak pointer to the component

api/sixtyfps-rs/lib.rs

@@ -20,7 +20,7 @@ sixtyfps::sixtyfps!{
 }
 fn main() {
 #   return; // Don't run a window in an example
-    HelloWorld::default().run()
+    HelloWorld::new().run()
 }
 ```
 
@@ -56,7 +56,7 @@ Then in your main file
 ```ignore
 sixtyfps::include_modules!();
 fn main() {
-    HelloWorld::default().run()
+    HelloWorld::new().run()
 }
 ```
 */

api/sixtyfps-rs/repeater.rs

@@ -1,4 +1,6 @@
 use core::cell::RefCell;
+use core::pin::Pin;
+use std::rc::Rc;
 
 /// Component that can be instantiated by a repeater.
 pub trait RepeatedComponent: sixtyfps_corelib::abi::datastructures::Component {
@@ -11,9 +13,14 @@ pub trait RepeatedComponent: sixtyfps_corelib::abi::datastructures::Component {
 
 /// This field is put in a component when using the `for` syntax
 /// It helps instantiating the components `C`
-#[derive(Default)]
 pub struct Repeater<C> {
-    components: RefCell<Vec<core::pin::Pin<Box<C>>>>,
+    components: RefCell<Vec<Pin<Rc<C>>>>,
+}
+
+impl<C> Default for Repeater<C> {
+    fn default() -> Self {
+        Repeater { components: Default::default() }
+    }
 }
 
 impl<Data, C> Repeater<C>
@@ -21,7 +28,7 @@ where
     C: RepeatedComponent<Data = Data>,
 {
     /// Called when the model is changed
-    pub fn update_model<'a>(&self, data: impl Iterator<Item = Data>, init: impl Fn() -> C)
+    pub fn update_model<'a>(&self, data: impl Iterator<Item = Data>, init: impl Fn() -> Pin<Rc<C>>)
     where
         Data: 'a,
     {
@@ -29,7 +36,7 @@ where
         for (i, d) in data.enumerate() {
             let c = init();
             c.update(i, d);
-            self.components.borrow_mut().push(Box::pin(c));
+            self.components.borrow_mut().push(c);
         }
     }
 

examples/rusttest/src/main.rs

@@ -127,7 +127,7 @@ Hello := Rectangle {
 }
 
 fn main() {
-    let mut app = Hello::default();
+    let app = Hello::new();
     app.plus_clicked.set_handler(|context, ()| {
         let app = context.get_component::<Hello>().unwrap();
         let counter = Hello::field_offsets().counter.apply_pin(app);

examples/rusttest2/src/main.rs

@@ -3,7 +3,7 @@
 sixtyfps::include_modules!();
 
 fn main() {
-    let mut app = Hello::default();
+    let app = Hello::new();
 
     app.plus_clicked.set_handler(|context, ()| {
         let app = context.get_component::<Hello>().unwrap();

examples/rustwasmtest/src/lib.rs

@@ -10,5 +10,5 @@ pub fn wasm_main() {
     #[cfg(debug_assertions)]
     console_error_panic_hook::set_once();
 
-    Hello::default().run();
+    Hello::new().run();
 }

sixtyfps_compiler/generator/rust.rs

@@ -115,7 +115,6 @@ pub fn generate(component: &Rc<Component>, diag: &mut Diagnostics) -> Option<Tok
     let mut repeated_dynmodel_names = Vec::new();
     let mut repeated_visit_branch = Vec::new();
     let mut init = Vec::new();
-    let mut init_repeaters = Vec::new();
     super::build_array_helper(component, |item_rc, children_index| {
         let item = item_rc.borrow();
         if let Some(repeated) = &item.repeated {
@@ -166,11 +165,9 @@ pub fn generate(component: &Rc<Component>, diag: &mut Diagnostics) -> Option<Tok
             }
 
             if repeated.model.is_constant() {
-                init_repeaters.push(quote! {
+                init.push(quote! {
                     self_pinned.#repeater_id.update_model(#model, || {
-                        let mut new_comp = #rep_component_id::default();
+                        #rep_component_id::new(self_pinned.self_weak.get().unwrap().clone())
-                        new_comp.parent = self_pinned.self_weak.get().unwrap().clone();
-                        new_comp
                     });
                 });
                 repeated_visit_branch.push(quote!(
@@ -189,9 +186,7 @@ pub fn generate(component: &Rc<Component>, diag: &mut Diagnostics) -> Option<Tok
                                 );
                                 let context = &context;
                                 self_pinned.#repeater_id.update_model(#model, || {
-                                    let mut new_comp = #rep_component_id::default();
+                                    #rep_component_id::new(self_pinned.self_weak.get().unwrap().clone())
-                                    new_comp.parent = self_pinned.self_weak.get().unwrap().clone();
-                                    new_comp
                                 });
                             });
                         }
@@ -231,38 +226,37 @@ pub fn generate(component: &Rc<Component>, diag: &mut Diagnostics) -> Option<Tok
 
                 if matches!(item.lookup_property(k.as_str()), Type::Signal) {
                     init.push(quote!(
-                        self_.#rust_property.set_handler(|context, ()| {
+                        self_pinned.#rust_property.set_handler(|context, ()| {
                             let _self = context.get_component::<#component_id>().unwrap();
                             #tokens_for_expression;
                         });
                     ));
                 } else {
-                    if binding_expression.is_constant() {
+                    let setter = if binding_expression.is_constant() {
-                        let setter = property_set_value_tokens(
+                        property_set_value_tokens(
                             component,
                             &item_rc,
                             k,
                             quote!((#tokens_for_expression) as _),
-                        );
+                        )
-                        init.push(quote!(
-                            self_.#rust_property.#setter;
-                        ));
                     } else {
-                        let setter = property_set_binding_tokens(
+                        property_set_binding_tokens(
                             component,
                             &item_rc,
                             k,
-                            quote!(
+                            quote!({
-                                |context| {
+                                let self_weak = sixtyfps::re_exports::WeakPin::downgrade(self_pinned.clone());
-                                    let _self = context.get_component::<#component_id>().unwrap();
+                                move |context| {
+                                    let self_pinned = self_weak.upgrade().unwrap();
+                                    let _self = self_pinned.as_ref();
                                     (#tokens_for_expression) as _
                                 }
-                            ),
+                            }),
-                        );
+                        )
-                        init.push(quote!(
+                    };
-                            self_.#rust_property.#setter;
+                    init.push(quote!(
-                        ));
+                        self_pinned.#rust_property.#setter;
-                    }
+                    ));
                 }
             }
             item_names.push(field_name);
@@ -312,15 +306,10 @@ pub fn generate(component: &Rc<Component>, diag: &mut Diagnostics) -> Option<Tok
         ));
     } else {
         property_and_signal_accessors.push(quote! {
-            fn run(self) {
+            fn run(self : core::pin::Pin<std::rc::Rc<Self>>) {
                 use sixtyfps::re_exports::*;
                 let window = sixtyfps::create_window();
-                let self_pinned = Rc::pin(self);
+                window.run(VRef::new_pin(self.as_ref()));
-                self_pinned.self_weak.set(WeakPin::downgrade(self_pinned.clone()))
-                    .map_err(|_|())
-                    .expect("Can only be pinned once");
-                #(#init_repeaters)*
-                window.run(VRef::new_pin(self_pinned.as_ref()));
             }
         });
     };
@@ -349,25 +338,6 @@ pub fn generate(component: &Rc<Component>, diag: &mut Diagnostics) -> Option<Tok
             #(parent : sixtyfps::re_exports::WeakPin<#parent_component_type>,)*
         }
 
-        impl ::core::default::Default for #component_id {
-            fn default() -> Self {
-                #![allow(unused)]
-                use sixtyfps::re_exports::*;
-                ComponentVTable_static!(static VT for #component_id);
-                let mut self_ = Self {
-                    #(#item_names : ::core::default::Default::default(),)*
-                    #(#declared_property_vars : ::core::default::Default::default(),)*
-                    #(#declared_signals : ::core::default::Default::default(),)*
-                    #(#repeated_element_names : ::core::default::Default::default(),)*
-                    #(#repeated_dynmodel_names : ::core::default::Default::default(),)*
-                    self_weak : ::core::default::Default::default(),
-                    #(parent : sixtyfps::re_exports::WeakPin::<#parent_component_type>::default(),)*
-                };
-                #(#init)*
-                self_
-            }
-
-        }
         impl sixtyfps::re_exports::Component for #component_id {
             fn visit_children_item(self: ::core::pin::Pin<&Self>, index: isize, visitor: sixtyfps::re_exports::ItemVisitorRefMut) {
                 use sixtyfps::re_exports::*;
@@ -386,6 +356,27 @@ pub fn generate(component: &Rc<Component>, diag: &mut Diagnostics) -> Option<Tok
         }
 
         impl #component_id{
+            fn new(#(parent: sixtyfps::re_exports::WeakPin::<#parent_component_type>)*)
+                -> core::pin::Pin<std::rc::Rc<Self>>
+            {
+                #![allow(unused)]
+                use sixtyfps::re_exports::*;
+                ComponentVTable_static!(static VT for #component_id);
+                let mut self_ = Self {
+                    #(#item_names : ::core::default::Default::default(),)*
+                    #(#declared_property_vars : ::core::default::Default::default(),)*
+                    #(#declared_signals : ::core::default::Default::default(),)*
+                    #(#repeated_element_names : ::core::default::Default::default(),)*
+                    #(#repeated_dynmodel_names : ::core::default::Default::default(),)*
+                    self_weak : ::core::default::Default::default(),
+                    #(parent : parent as sixtyfps::re_exports::WeakPin::<#parent_component_type>,)*
+                };
+                let self_pinned = std::rc::Rc::pin(self_);
+                self_pinned.self_weak.set(WeakPin::downgrade(self_pinned.clone())).map_err(|_|())
+                    .expect("Can only be pinned once");
+                #(#init)*
+                self_pinned
+            }
             #(#property_and_signal_accessors)*
         }
 

sixtyfps_runtime/corelib/abi/signals.rs

@@ -6,6 +6,7 @@ but then it should also be renamed everywhere, including in the language grammar
 */
 
 use super::properties::EvaluationContext;
+use core::cell::Cell;
 
 /// A Signal that can be connected to a handler.
 ///
@@ -15,7 +16,7 @@ use super::properties::EvaluationContext;
 #[repr(C)]
 pub struct Signal<Arg> {
     /// FIXME: Box<dyn> is a fat object and we probaly want to put an erased type in there
-    handler: Option<Box<dyn Fn(&EvaluationContext, Arg)>>,
+    handler: Cell<Option<Box<dyn Fn(&EvaluationContext, Arg)>>>,
 }
 
 impl<Arg> Signal<Arg> {
@@ -23,16 +24,18 @@ impl<Arg> Signal<Arg> {
     ///
     /// The constext must be a context corresponding to the component in which the signal is contained.
     pub fn emit(&self, context: &EvaluationContext, a: Arg) {
-        if let Some(h) = &self.handler {
+        if let Some(h) = self.handler.take() {
             h(context, a);
+            assert!(self.handler.take().is_none(), "Signal Handler set while emitted");
+            self.handler.set(Some(h))
         }
     }
 
     /// Set an handler to be called when the signal is emited
     ///
     /// There can only be one single handler per signal.
-    pub fn set_handler(&mut self, f: impl Fn(&EvaluationContext, Arg) + 'static) {
+    pub fn set_handler(&self, f: impl Fn(&EvaluationContext, Arg) + 'static) {
-        self.handler = Some(Box::new(f));
+        self.handler.set(Some(Box::new(f)));
     }
 }
 
@@ -57,7 +60,7 @@ fn signal_simple_test() {
         fn compute_layout(self: Pin<&Self>, _: &crate::EvaluationContext) {}
     }
     use crate::abi::datastructures::ComponentVTable;
-    let mut c = Component::default();
+    let c = Component::default();
     c.clicked.set_handler(|c, ()| unsafe {
         (*(c.component.as_ptr() as *const Component)).pressed.set(true)
     });

tests/cases/arithmetic_expr.60

@@ -18,7 +18,7 @@ assert(instance.get_t4() == 3 + - 5 - 8 - -9 * - - - 120);
 
 
 ```rust
-let instance = Box::pin(TestCase::default());
+let instance = TestCase::new();
 let instance = instance.as_ref();
 assert_eq!(instance.get_t1(), 4 + 3 * 2 + 2 - 50 - 2);
 assert_eq!(instance.get_t2(), 500 / 2 * 30 - 1);

tests/cases/bool.60

@@ -11,7 +11,7 @@ assert(!instance.get_falsevar());
 
 
 ```rust
-let instance = Box::pin(TestCase::default());
+let instance = TestCase::new();
 let instance = instance.as_ref();
 assert!(instance.get_truevar(), 1);
 assert!(!instance.get_falsevar(), 1);

tests/cases/cast_conditional.60

@@ -21,7 +21,7 @@ assert(instance.get_s1() == "123");
 
 
 ```rust
-let instance = Box::pin(TestCase::default());
+let instance = TestCase::new();
 let instance = instance.as_ref();
 instance.set_condition(true);
 assert_eq!(instance.get_s1(), "abc");

tests/cases/color.60

@@ -27,7 +27,7 @@ assert(t.get_b1() != t.get_r5());
 
 
 ```rust
-let t = Box::pin(Test::default());
+let t = Test::new();
 let t = t.as_ref();
 assert_eq!(t.get_r1(), t.get_r2());
 assert_eq!(t.get_r1(), t.get_r3());

tests/cases/comparison_expr.60

@@ -58,7 +58,7 @@ assert(instance.get_t6() == true);
 
 
 ```rust
-let instance = Box::pin(TestCase::default());
+let instance = TestCase::new();
 let instance = instance.as_ref();
 
 assert_eq!(instance.get_t1(), true);

tests/cases/conditional_expr.60

@@ -20,7 +20,7 @@ assert(instance.get_test_value2() == 3);
 
 
 ```rust
-let instance = Box::pin(TestCase::default());
+let instance = TestCase::new();
 let instance = instance.as_ref();
 instance.set_condition(true);
 assert_eq!(instance.get_test_value(), 1);

tests/cases/signal_handler.60

@@ -14,7 +14,7 @@ assert(instance.get_signal_emission_count() == 1);
 
 
 ```rust
-let instance = Box::pin(TestCase::default());
+let instance = TestCase::new();
 let instance = instance.as_ref();
 instance.set_signal_emission_count(0);
 assert_eq!(instance.get_signal_emission_count(), 0);

tests/cases/simple.60

@@ -8,7 +8,7 @@ TestCase instance;
 ```
 
 ```rust
-TestCase::default();
+TestCase::new();
 ```
 
 ```js