xilem_html: Add SetAttr trait (experiment)

crates/xilem_html/src/element/elements.rs

@@ -96,6 +96,17 @@ macro_rules! element {
                 self.0.message(id_path, state, message, app_state)
             }
         }
+
+        impl<ViewSeq> crate::set_attr::SetAttr for $ty_name<ViewSeq> {
+            #[deny(unconditional_recursion)]
+            fn set_attr(
+                &mut self,
+                name: impl Into<std::borrow::Cow<'static, str>>,
+                value: impl Into<std::borrow::Cow<'static, str>>,
+            ) {
+                self.0.set_attr(name, value);
+            }
+        }
     };
 }
 

crates/xilem_html/src/element/mod.rs

@@ -5,6 +5,7 @@
 use crate::{
     context::{ChangeFlags, Cx},
     view::{DomElement, Pod, View, ViewMarker, ViewSequence},
+    SetAttr,
 };
 
 use std::{borrow::Cow, cmp::Ordering, collections::BTreeMap, fmt};
@@ -257,6 +258,17 @@ where
     }
 }
 
+impl<El, ViewSeq> SetAttr for Element<El, ViewSeq> {
+    #[deny(unconditional_recursion)]
+    fn set_attr(
+        &mut self,
+        name: impl Into<Cow<'static, str>>,
+        value: impl Into<Cow<'static, str>>,
+    ) {
+        self.set_attr(name, value);
+    }
+}
+
 #[cfg(feature = "typed")]
 fn set_attribute(element: &web_sys::Element, name: &str, value: &str) {
     // we have to special-case `value` because setting the value using `set_attribute`

crates/xilem_html/src/event/events.rs

@@ -107,6 +107,21 @@ macro_rules! event {
                 self.inner.message(id_path, state, message, app_state)
             }
         }
+
+        impl<T, A, V, F, OA> crate::set_attr::SetAttr for $ty_name<T, A, V, F, OA>
+        where
+            V: crate::view::View<T, A> + crate::set_attr::SetAttr,
+            V::Element: 'static,
+        {
+            #[deny(unconditional_recursion)]
+            fn set_attr(
+                &mut self,
+                name: impl Into<std::borrow::Cow<'static, str>>,
+                value: impl Into<std::borrow::Cow<'static, str>>,
+            ) {
+                self.inner.set_attr(name, value);
+            }
+        }
     };
 }
 

crates/xilem_html/src/event/mod.rs

@@ -4,7 +4,7 @@
 #[cfg(feature = "typed")]
 pub mod events;
 
-use std::{any::Any, marker::PhantomData, ops::Deref};
+use std::{any::Any, borrow::Cow, marker::PhantomData, ops::Deref};
 
 use gloo::events::{EventListener, EventListenerOptions};
 use wasm_bindgen::{JsCast, UnwrapThrowExt};
@@ -13,6 +13,7 @@ use xilem_core::{Id, MessageResult};
 use crate::{
     context::{ChangeFlags, Cx},
     view::{DomNode, View, ViewMarker},
+    SetAttr,
 };
 
 /// Wraps a [`View`] `V` and attaches an event listener.
@@ -123,6 +124,20 @@ where
     }
 }
 
+impl<E, V, F> SetAttr for OnEvent<E, V, F>
+where
+    V: SetAttr,
+{
+    #[deny(unconditional_recursion)]
+    fn set_attr(
+        &mut self,
+        name: impl Into<Cow<'static, str>>,
+        value: impl Into<Cow<'static, str>>,
+    ) {
+        self.child.set_attr(name, value);
+    }
+}
+
 // Attach an event listener to the child's element
 pub fn on_event<E, V, F>(name: &'static str, child: V, callback: F) -> OnEvent<E, V, F> {
     OnEvent::new(name, child, callback)

crates/xilem_html/src/lib.rs

@@ -13,6 +13,7 @@ mod context;
 mod element;
 mod event;
 mod one_of;
+mod set_attr;
 mod view;
 #[cfg(feature = "typed")]
 mod view_ext;
@@ -29,6 +30,7 @@ pub use element::{element, Element, ElementState};
 pub use event::events;
 pub use event::{on_event, Action, Event, OnEvent, OnEventState, OptionalAction};
 pub use one_of::{OneOf2, OneOf3, OneOf4, OneOf5, OneOf6, OneOf7, OneOf8};
+pub use set_attr::SetAttr;
 pub use view::{
     Adapt, AdaptState, AdaptThunk, AnyView, Memoize, Pod, View, ViewMarker, ViewSequence,
 };

crates/xilem_html/src/set_attr.rs

@@ -0,0 +1,17 @@
+use std::borrow::Cow;
+
+pub trait SetAttr {
+    fn set_attr(&mut self, name: impl Into<Cow<'static, str>>, value: impl Into<Cow<'static, str>>);
+
+    fn attr(
+        mut self,
+        name: impl Into<Cow<'static, str>>,
+        value: impl Into<Cow<'static, str>>,
+    ) -> Self
+    where
+        Self: Sized,
+    {
+        self.set_attr(name, value);
+        self
+    }
+}

crates/xilem_html/src/view.rs

@@ -8,7 +8,7 @@ use std::{any::Any, borrow::Cow, ops::Deref};
 
 use xilem_core::{Id, MessageResult};
 
-use crate::{context::Cx, ChangeFlags};
+use crate::{context::Cx, ChangeFlags, SetAttr};
 
 mod sealed {
     pub trait Sealed {}
@@ -222,3 +222,30 @@ impl<T, A> View<T, A> for Cow<'static, str> {
 fn new_text(text: &str) -> web_sys::Text {
     web_sys::Text::new_with_data(text).unwrap()
 }
+
+impl<ParentT, ParentA, ChildT, ChildA, V, F> SetAttr
+    for Adapt<ParentT, ParentA, ChildT, ChildA, V, F>
+where
+    V: SetAttr,
+{
+    fn set_attr(
+        &mut self,
+        name: impl Into<Cow<'static, str>>,
+        value: impl Into<Cow<'static, str>>,
+    ) {
+        self.child.set_attr(name, value);
+    }
+}
+
+impl<ParentT, ChildT, V, F> SetAttr for AdaptState<ParentT, ChildT, V, F>
+where
+    V: SetAttr,
+{
+    fn set_attr(
+        &mut self,
+        name: impl Into<Cow<'static, str>>,
+        value: impl Into<Cow<'static, str>>,
+    ) {
+        self.child.set_attr(name, value);
+    }
+}