added is_none and is_some

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### New Functions 🚀
 
+- `is_none`
+- `is_some`
 - `use_raf_fn`
 
 ### Braking Changes 🛠

docs/book/src/SUMMARY.md

@@ -63,6 +63,8 @@
 
 # Utilities
 
+- [is_none](utilities/is_none.md)
+- [is_some](utilities/is_some.md)
 - [use_cycle_list](utilities/use_cycle_list.md)
 - [use_debounce_fn](utilities/use_debounce_fn.md)
 - [use_supported](utilities/use_supported.md)

docs/book/src/utilities/is_none.md

@@ -0,0 +1,3 @@
+# is_none
+
+<!-- cmdrun python3 ../extract_doc_comment.py is_none  -->

docs/book/src/utilities/is_some.md

@@ -0,0 +1,3 @@
+# is_some
+
+<!-- cmdrun python3 ../extract_doc_comment.py is_some  -->

examples/Cargo.toml

@@ -2,6 +2,8 @@
 resolver = "2"
 
 members = [
+    "is_none",
+    "is_some",
     "on_click_outside",
     "use_abs",
     "use_active_element",

src/is_none.rs

@@ -0,0 +1,27 @@
+use crate::utils::use_derive_signal;
+use leptos::*;
+
+use_derive_signal!(
+    /// Reactive `Option::is_none()`.
+    ///
+    /// ## Usage
+    ///
+    /// ```
+    /// # use leptos::*;
+    /// # use leptos_use::is_none;
+    /// #
+    /// # #[component]
+    /// # fn Demo(cx: Scope) -> impl IntoView {
+    /// let (example, set_example) = create_signal(
+    ///     cx,
+    ///     if js_sys::Math::random() < 0.5 { Some("Example") } else { None }
+    /// );
+    ///
+    /// let is_empty = is_none(cx, example);
+    /// #
+    /// # view! { cx, }
+    /// # }
+    /// ```
+    is_none<Option<T>, T: 'static> -> bool
+    |value| value.is_none()
+);

src/is_some.rs

@@ -0,0 +1,27 @@
+use crate::utils::use_derive_signal;
+use leptos::*;
+
+use_derive_signal!(
+    /// Reactive `Option::is_some()`.
+    ///
+    /// ## Usage
+    ///
+    /// ```
+    /// # use leptos::*;
+    /// # use leptos_use::is_some;
+    /// #
+    /// # #[component]
+    /// # fn Demo(cx: Scope) -> impl IntoView {
+    /// let (example, set_example) = create_signal(
+    ///     cx,
+    ///     if js_sys::Math::random() < 0.5 { Some("Example") } else { None }
+    /// );
+    ///
+    /// let not_empty = is_some(cx, example);
+    /// #
+    /// # view! { cx, }
+    /// # }
+    /// ```
+    is_some<Option<T>, T: 'static> -> bool
+    |value| value.is_some()
+);

src/lib.rs

@@ -21,6 +21,8 @@ cfg_if! { if #[cfg(web_sys_unstable_apis)] {
 }}
 
 mod on_click_outside;
+mod is_none;
+mod is_some;
 mod use_active_element;
 mod use_breakpoints;
 mod use_color_mode;
@@ -56,6 +58,8 @@ mod watch_throttled;
 mod whenever;
 
 pub use on_click_outside::*;
+pub use is_none::*;
+pub use is_some::*;
 pub use use_active_element::*;
 pub use use_breakpoints::*;
 pub use use_color_mode::*;

src/utils/mod.rs

@@ -3,9 +3,11 @@ mod filters;
 mod is;
 mod js_value_from_to_string;
 mod pausable;
+mod use_derive_signal;
 
 pub use clonable_fn::*;
 pub use filters::*;
 pub use is::*;
 pub(crate) use js_value_from_to_string::*;
 pub use pausable::*;
+pub(crate) use use_derive_signal::*;

src/utils/use_derive_signal.rs

@@ -0,0 +1,18 @@
+macro_rules! use_derive_signal {
+    (
+        $(#[$outer:meta])*
+        $name:ident <$inner_signal_type:tt $(< $( $inner_type_param:tt ),+ >)? $(, $( $type_param:tt $( : $first_bound:tt $(+ $rest_bound:tt)* )? ),+ )? > -> $return_type:tt
+        $($body:tt)+
+    ) => {
+        $(#[$outer])*
+        pub fn $name<V $(, $( $type_param ),* )? >(cx: Scope, value: V) -> Signal<$return_type>
+        where
+            V: Into<MaybeSignal<$inner_signal_type $(< $( $inner_type_param ),+ >)?>> $(, $( $type_param $( : $first_bound $(+ $rest_bound)* )? ),+ )?
+        {
+            let value = value.into();
+            Signal::derive(cx, move || value.with($($body)+))
+        }
+    };
+}
+
+pub(crate) use use_derive_signal;