Readable and Writable helpers for String, HashMap and HashSet (#4834)

* Add more read/write methods for string signals

* add helpers for HashMap and HashSet as well

* fix typo

* fix conflicting string and str extensions

* fix counters example

examples/08-apis/control_focus.rs

@@ -56,7 +56,7 @@ fn app() -> Element {
                 input {
                     r#type: "number",
                     value: "{i}",
-                    onmounted: move |cx| elements.write().push(cx.data()),
+                    onmounted: move |cx| elements.push(cx.data()),
                     oninput: move |_| running.set(false),
                 }
             }

examples/08-apis/file_upload.rs

@@ -27,12 +27,12 @@ fn app() -> Element {
         for file in files {
             let filename = file.name();
             if let Ok(contents) = file.read_string().await {
-                files_uploaded.write().push(UploadedFile {
+                files_uploaded.push(UploadedFile {
                     name: filename,
                     contents,
                 });
             } else {
-                files_uploaded.write().push(UploadedFile {
+                files_uploaded.push(UploadedFile {
                     name: filename,
                     contents: "Failed to read file".into(),
                 });
@@ -45,7 +45,7 @@ fn app() -> Element {
 
         h1 { "File Upload Example" }
         p { "Drop a .txt, .rs, or .js file here to read it" }
-        button { onclick: move |_| files_uploaded.write().clear(), "Clear files" }
+        button { onclick: move |_| files_uploaded.clear(), "Clear files" }
 
         div {
             label { r#for: "directory-upload", "Enable directory upload" }

examples/08-apis/window_popup.rs

@@ -15,7 +15,7 @@ fn app() -> Element {
     let handle = use_coroutine(move |mut rx: UnboundedReceiver<String>| async move {
         use futures_util::StreamExt;
         while let Some(message) = rx.next().await {
-            emails_sent.write().push(message);
+            emails_sent.push(message);
         }
     });