Improve the type safety and ergonomics of bind_event.

* Add the triggering signal as a parameter. This ensures that
  We always call get on the signal to trigger the effect.

* Rename the method to bind_trigger to better reflect what it
  is doing.

.gitignore

@@ -1,2 +1,3 @@
 /target
 /Cargo.lock
+.jj/

src/lib.rs

@@ -11,7 +11,7 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-use std::marker::PhantomData;
+use std::{marker::PhantomData, rc::Rc};
 
 use sycamore::prelude::*;
 
@@ -53,11 +53,15 @@ where
         self.signal
     }
 
-    pub fn bind_event<F>(&'ctx self, cx: Scope<'ctx>, message_fn: F)
-    where
-        F: Fn() -> Msg + 'ctx,
+    pub fn bind_trigger<F, Val>(
+        &'ctx self,
+        cx: Scope<'ctx>,
+        trigger: &'ctx ReadSignal<Val>,
+        message_fn: F,
+    ) where
+        F: Fn(Rc<Val>) -> Msg + 'ctx,
     {
-        create_effect(cx, move || self.dispatch(message_fn()));
+        create_effect(cx, move || self.dispatch(message_fn(trigger.get())));
     }
 }
 

src/tests/mod.rs

@@ -65,7 +65,7 @@ fn test_state_effect_flow() {
         create_child_scope(cx, |cx| {
             let form_val = create_signal(cx, handler.read_signal().get_untracked().value_one.clone());
 
-            handler.bind_event(cx, || Msg::UpdateOne((*form_val.get()).clone()));
+            handler.bind_trigger(cx, form_val, |val| Msg::UpdateOne((*val).clone()));
 
             form_val.set("bar".to_owned());
 
@@ -74,7 +74,7 @@ fn test_state_effect_flow() {
             create_child_scope(cx, |cx| {
                 let form_val = create_signal(cx, 0);
 
-                handler.bind_event(cx, || Msg::UpdateTwo(*form_val.get()));
+                handler.bind_trigger(cx, form_val, |val| Msg::UpdateTwo(*val));
                 form_val.set(1);
                 assert_eq!(handler.read_signal().get_untracked().value_two, 1);
             });