feat: unsafe React.useEffect

Author: EqualMa

src/lib.rs

@@ -1,9 +1,11 @@
 mod element;
 mod macro_import;
+mod use_effect;
 mod use_ref;
 mod use_state;
 
 pub use element::*;
+pub use use_effect::*;
 pub use use_ref::*;
 pub use use_state::*;
 

src/use_effect.rs

@@ -0,0 +1,30 @@
+use wasm_bindgen::prelude::*;
+
+crate::macro_import::wasm_bindgen_react! {
+    /// `React.useEffect(effect, dependencies)`
+    ///
+    /// # Safety
+    ///
+    /// `effect` closure will be passed to js runtime
+    /// and called ( or never called ) asynchronously by React.
+    ///
+    /// As [`wasm_bindgen`](https://rustwasm.github.io/docs/wasm-bindgen/reference/passing-rust-closures-to-js.html) describes,
+    ///
+    /// > Once a Closure is dropped, it will deallocate its internal memory
+    /// > and invalidate the corresponding JavaScript function
+    /// > so that any further attempts to invoke it raise an exception.
+    ///
+    /// Rust compiler can only ensure this closure is not dropped before `use_effect` returned,
+    /// so it's up to you to make sure the closure lived longer enough
+    /// to be valid in the component life time.
+    ///
+    /// Thus, this function is marked `unsafe` as a warning.
+    #[wasm_bindgen(js_namespace = React, js_name = useEffect)]
+    pub unsafe fn use_effect(effect: &Closure<dyn FnMut()>, dependencies: Option<Box<[JsValue]>>);
+
+    #[wasm_bindgen(js_namespace = React, js_name = useEffect)]
+    pub unsafe fn use_effect_with_clean(
+        effect: &Closure<dyn FnMut() -> JsValue>,
+        dependencies: Option<Box<[JsValue]>>,
+    );
+}