wip: failed to use macro to define wasm_bindgen extern c

Author: EqualMa

src/helpers.rs

@@ -0,0 +1,112 @@
+use wasm_bindgen::prelude::*;
+
+macro_rules! define_react_use_state_for_type {
+    ( value: $type_value:ty, $($t:tt)+ ) => {
+        define_react_use_state_for_type!(
+            input: $type_value,
+            output: $type_value,
+            $($t)+
+        );
+    };
+    (
+        input: $type_input:ty,
+        output: $type_output:ty,
+        object: $name_object:ident,
+        setter: $name_setter:ident,
+        use_state: $name_use:ident,
+        use_state_with: $name_use_with:ident,
+        auto_clean: $name_clean:ident,
+        auto_clean_with: $name_clean_with:ident
+        $(,)?
+    ) => {
+        #[derive(Debug, Clone)]
+        pub type $name_object;
+        #[wasm_bindgen(structural, method, getter)]
+        fn value(this: &$name_object) -> $type_output;
+        #[wasm_bindgen(structural, method, getter)]
+        fn setter(this: &$name_object) -> $name_setter;
+
+        #[derive(Debug, Clone)]
+        pub type $name_setter;
+        #[wasm_bindgen(structural, method)]
+        fn set_state(this: &$name_setter, value: $type_input);
+        /// Closure `get_value_from_old` will be called immediately,
+        /// thus it is safe to use reference here
+        ///
+        /// Closure get_value_from_old will be called only once
+        #[wasm_bindgen(structural, method, js_name = "set_state")]
+        fn set_state_with(
+            this: &$name_setter,
+            get_value_from_old: &mut dyn FnMut($type_output) -> $type_input,
+        );
+
+        #[wasm_bindgen(js_name = "use_state_object")]
+        fn $name_use(initial_value: $type_input) -> $name_object;
+
+        #[wasm_bindgen(js_name = "use_state_object")]
+        fn $name_use_with(
+            initial_value: &mut dyn FnMut() -> $type_input,
+        ) -> $name_object;
+
+        #[wasm_bindgen(js_name = "use_state_auto_clean")]
+        fn $name_clean(
+            initial_value: $type_input,
+            free: &Closure<dyn FnMut($type_output)>,
+        ) -> $name_object;
+
+        #[wasm_bindgen(js_name = "use_state_auto_clean")]
+        fn $name_clean_with(
+            get_initial_value: &mut dyn FnMut() -> $type_input,
+            free: &Closure<dyn FnMut($type_output)>,
+        ) -> $name_object;
+    };
+}
+
+// #[cfg_attr(
+//     feature = "import-react",
+//     wasm_bindgen(inline_js = r#"
+// import * as React from "react";
+// export function use_state_object(initial_value) {
+//     const [state, set_state] = React.useState(initial_value);
+//     return { value: state, setter: { set_state } };
+// }
+// export function use_state_auto_clean(initial_value, clean) {
+//     const obj = use_state_object(initial_value);
+//     const state = obj.value;
+//     React.useEffect(() => { clean(state) }, [state]);
+// }
+// "#)
+// )]
+// #[cfg_attr(
+//     not(feature = "import-react"),
+//     wasm_bindgen(inline_js = r#"
+// export function use_state_object(initial_value) {
+//     const [state, set_state] = React.useState(initial_value);
+//     return { value: state, setter: { set_state } };
+// }
+// export function use_state_auto_clean(initial_value, clean) {
+//     const obj = use_state_object(initial_value);
+//     const state = obj.value;
+//     React.useEffect(() => { clean(state) }, [state]);
+// }
+// "#)
+// )]
+
+macro_rules! ttt {
+    () => {
+        type Element;
+    };
+}
+
+#[wasm_bindgen]
+extern "C" {
+    define_react_use_state_for_type! {
+        value: usize,
+        object: UseStateUsizeObject,
+        setter: UseStateUsizeObjectSetter,
+        use_state: use_state_object_usize,
+        use_state_with: use_state_object_usize_with,
+        auto_clean: use_state_usize_auto_clean,
+        auto_clean_with: use_state_usize_auto_clean_with,
+    }
+}