Macro update

Changed files (1)

• modified src/lib.rs

Diff

diff --git a/src/lib.rs b/src/lib.rsindex cd7c3fa..d197915 100644--- a/src/lib.rs+++ b/src/lib.rs@@ -1,6 +1,6 @@ use proc_macro::TokenStream; use quote::quote;-use syn::{parse_macro_input, FnArg, ItemFn, LitStr};+use syn::{parse_macro_input, ItemFn, LitStr};  /// Make sures a function is registerd in JS for a given callback in the /// Kaja Web Framework (WebAssembly, Rust).@@ -11,7 +11,7 @@ use syn::{parse_macro_input, FnArg, ItemFn, LitStr}; /// struct SomeClickEvent { ///     índex: usize, /// }-+/// /// #[callback("someClickCallback")] /// fn some_on_click_function(event: SomeClickEvent) { ///     log!("event.índex: {:?}", event.índex);@@ -26,80 +26,56 @@ use syn::{parse_macro_input, FnArg, ItemFn, LitStr}; /// ``` #[proc_macro_attribute] pub fn callback(attr: TokenStream, item: TokenStream) -> TokenStream {-    let js_name = parse_macro_input!(attr as LitStr).value();+    let js_name_lit = parse_macro_input!(attr as LitStr);     let input_fn = parse_macro_input!(item as ItemFn);-     let fn_name = &input_fn.sig.ident;+    let fn_name_lit = LitStr::new(&fn_name.to_string(), fn_name.span());     let vis = &input_fn.vis;     let sig = &input_fn.sig;     let fn_block = &input_fn.block; -    // Extract single argument type-    let arg = input_fn-        .sig-        .inputs-        .first()-        .expect("callback must have one argument");--    let arg_type = match arg {-        FnArg::Typed(pat_type) => &pat_type.ty,-        _ => panic!("expected typed argument"),-    };-     let register_fn_name = syn::Ident::new(&format!("{}_register", fn_name), fn_name.span());--    let expanded = quote! {-        #vis #sig #fn_block--        pub fn #register_fn_name() {-            use wasm_bindgen::closure::Closure;-            use wasm_bindgen::JsCast;--            let window = web_sys::window();--            if window.is_none() {-                gloo::console::log!("Callback error: {}. No window.", fn_name);-                return;-            }--            let window = window.unwrap();-            let callback_js_closure = Closure::<dyn FnMut(wasm_bindgen::JsValue)>::new(|val| {-                let event: #arg_type =-                    serde_wasm_bindgen::from_value(val);--                if event.is_err() {-                    gloo::console::log!("Callback error: {}. Wrong argument type: {}", fn_name, event.err().unwrap());-                    return;+    let register_fn_name_lit = LitStr::new(&register_fn_name.to_string(), register_fn_name.span());++    let expanded = match input_fn.sig.inputs.len() {+        0 => {+            // No argument: ignore the JsValue passed from JS and call the function directly.+            quote! {+                #vis #sig #fn_block++                #[wasm_bindgen]+                pub fn #register_fn_name() {+                    use wasm_bindgen::closure::Closure;+                    use wasm_bindgen::JsCast;+                    use js_sys::{Array, Object, Reflect};+                    use wasm_bindgen::JsValue;++                    if let Some(window) = web_sys::window() {+                        let cb = Closure::<dyn FnMut(wasm_bindgen::JsValue)>::new(|_val| {+                            #fn_name();+                        });++                        let _ = Reflect::set(+                            window.as_ref(),+                            &JsValue::from_str(#register_fn_name_lit),+                            cb.as_ref().unchecked_ref(),+                        );++                        let key = JsValue::from_str(#js_name_lit);+                        let _ = Reflect::set(window.as_ref(), &key, cb.as_ref().unchecked_ref());+                        cb.forget();+                    }                 }--                let event = event.unwrap();-                #fn_name(event);-            });--            let set = ::js_sys::Reflect::set(-                &window,-                &#js_name.into(),-                cb.as_ref().unchecked_ref(),-            );--            if set.is_err() {-                let err = set.err().unwrap();--                gloo::console::log!(r#"Callback init error: {}, failed to set property on window.-                    Needed in order to have callback available in JS land."#, err);--                return;             }--            cb.forget();         }--        inventory::submit! {-            CallbackRegistration {-                register: #register_fn_name-            }+        _ => {+            // More than one argument is not supported by this macro.+            return TokenStream::from(quote! {+                compile_error!("#[callback(...)] only supports functions with 0 arguments");+            });         }     }; +    eprintln!("generated macro expansion:\n{}", expanded);     TokenStream::from(expanded) }