Wrap HtmlElement inside TemplateResult (#10)

examples/components/src/main.rs

@@ -2,7 +2,7 @@
 
 use maple_core::prelude::*;
 
-pub fn MyComponent(num: StateHandle<i32>) -> HtmlElement {
+pub fn MyComponent(num: StateHandle<i32>) -> TemplateResult {
     template! {
         div(class="my-component") {
             # "My component"

maple-core-macro/src/component.rs

@@ -20,7 +20,7 @@ impl ToTokens for Component {
     fn to_tokens(&self, tokens: &mut TokenStream) {
         let Component { expr_call } = self;
 
-        let quoted = quote! { #expr_call };
+        let quoted = quote! { ::maple_core::TemplateResult::inner_element(&#expr_call) };
 
         tokens.extend(quoted);
     }

maple-core-macro/src/lib.rs

@@ -77,7 +77,7 @@ pub fn template(input: TokenStream) -> TokenStream {
     let input = parse_macro_input!(input as element::Element);
 
     let quoted = quote! {
-        { #input }
+        ::maple_core::TemplateResult::new(#input)
     };
 
     TokenStream::from(quoted)

maple-core-macro/tests/ui/component-fail.rs

@@ -2,7 +2,7 @@
 
 use maple_core::prelude::*;
 
-fn Component() -> HtmlElement {
+fn Component() -> TemplateResult {
     template! {
         div
     }

maple-core-macro/tests/ui/component-pass.rs

@@ -2,7 +2,7 @@
 
 use maple_core::prelude::*;
 
-pub fn Component() -> HtmlElement {
+pub fn Component() -> TemplateResult {
     template! {
         div
     }

maple-core/src/lib.rs

@@ -13,20 +13,40 @@ pub mod reactive;
 use web_sys::HtmlElement;
 
 /// Render an [`HtmlElement`] into the DOM.
-pub fn render(element: HtmlElement) {
+pub fn render(template_result: TemplateResult) {
     let window = web_sys::window().unwrap();
     let document = window.document().unwrap();
-    document.body().unwrap().append_child(&element).unwrap();
+    document
+        .body()
+        .unwrap()
+        .append_child(&template_result.element)
+        .unwrap();
+}
+
+/// The result of the `template!` macro. Should not be used directly.
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct TemplateResult {
+    element: HtmlElement,
+}
+
+impl TemplateResult {
+    /// Create a new `TemplateResult` from an [`HtmlElement`].
+    pub fn new(element: HtmlElement) -> Self {
+        Self { element }
+    }
+
+    pub fn inner_element(&self) -> HtmlElement {
+        self.element.clone()
+    }
 }
 
 /// The maple prelude.
 pub mod prelude {
     pub use crate::reactive::{
-        create_effect, create_memo, create_signal, untracked, SetStateHandle, StateHandle,
+        create_effect, create_memo, create_selector, create_signal, untracked, SetStateHandle,
+        StateHandle,
     };
-    pub use crate::render;
+    pub use crate::{render, TemplateResult};
 
     pub use maple_core_macro::template;
-
-    pub use web_sys::HtmlElement;
 }

maple-core/src/reactive.rs

@@ -154,7 +154,7 @@ where
 /// assert_eq!(*double(), 2);
 ///
 /// set_state(2);
-/// assert_eq!(*double(), 2); // double value should still be true because state() was inside untracked
+/// assert_eq!(*double(), 2); // double value should still be old value because state() was inside untracked
 /// ```
 pub fn untracked<F, Out>(f: F) -> Out
 where