diff --git a/CHANGELOG.md b/CHANGELOG.md
index c94e8e9..6150878 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,12 @@
The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+## [Unreleased] -
+
+### New Functions 🚀
+
+- `sync_signal`
+
## [0.10.6] - 2024-04-02
### Fixes 🍕
diff --git a/docs/book/src/SUMMARY.md b/docs/book/src/SUMMARY.md
index e01bce2..51ca13f 100644
--- a/docs/book/src/SUMMARY.md
+++ b/docs/book/src/SUMMARY.md
@@ -87,6 +87,7 @@
- [signal_debounced](reactivity/signal_debounced.md)
- [signal_throttled](reactivity/signal_throttled.md)
+- [sync_signal](reactivity/sync_signal.md)
# Iterable
diff --git a/docs/book/src/reactivity/sync_signal.md b/docs/book/src/reactivity/sync_signal.md
new file mode 100644
index 0000000..0a3f77b
--- /dev/null
+++ b/docs/book/src/reactivity/sync_signal.md
@@ -0,0 +1,3 @@
+# sync_signal
+
+
diff --git a/examples/Cargo.toml b/examples/Cargo.toml
index 3bd37f5..4d56bbf 100644
--- a/examples/Cargo.toml
+++ b/examples/Cargo.toml
@@ -5,6 +5,7 @@ members = [
"on_click_outside",
"signal_debounced",
"signal_throttled",
+ "sync_signal",
"use_abs",
"use_active_element",
"use_and",
diff --git a/examples/sync_signal/Cargo.toml b/examples/sync_signal/Cargo.toml
new file mode 100644
index 0000000..0eae2b1
--- /dev/null
+++ b/examples/sync_signal/Cargo.toml
@@ -0,0 +1,16 @@
+[package]
+name = "sync_signal"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+leptos = { version = "0.6", features = ["nightly", "csr"] }
+console_error_panic_hook = "0.1"
+console_log = "1"
+log = "0.4"
+leptos-use = { path = "../..", features = ["docs"] }
+web-sys = "0.3"
+
+[dev-dependencies]
+wasm-bindgen = "0.2"
+wasm-bindgen-test = "0.3.0"
diff --git a/examples/sync_signal/README.md b/examples/sync_signal/README.md
new file mode 100644
index 0000000..aab326e
--- /dev/null
+++ b/examples/sync_signal/README.md
@@ -0,0 +1,23 @@
+A simple example for `sync_signal`.
+
+If you don't have it installed already, install [Trunk](https://trunkrs.dev/) and [Tailwind](https://tailwindcss.com/docs/installation)
+as well as the nightly toolchain for Rust and the wasm32-unknown-unknown target:
+
+```bash
+cargo install trunk
+npm install -D tailwindcss @tailwindcss/forms
+rustup toolchain install nightly
+rustup target add wasm32-unknown-unknown
+```
+
+Then, open two terminals. In the first one, run:
+
+```
+npx tailwindcss -i ./input.css -o ./style/output.css --watch
+```
+
+In the second one, run:
+
+```bash
+trunk serve --open
+```
\ No newline at end of file
diff --git a/examples/sync_signal/Trunk.toml b/examples/sync_signal/Trunk.toml
new file mode 100644
index 0000000..3e4be08
--- /dev/null
+++ b/examples/sync_signal/Trunk.toml
@@ -0,0 +1,2 @@
+[build]
+public_url = "/demo/"
\ No newline at end of file
diff --git a/examples/sync_signal/index.html b/examples/sync_signal/index.html
new file mode 100644
index 0000000..ae249a6
--- /dev/null
+++ b/examples/sync_signal/index.html
@@ -0,0 +1,7 @@
+
+
+
+
+
+
+
diff --git a/examples/sync_signal/input.css b/examples/sync_signal/input.css
new file mode 100644
index 0000000..bd6213e
--- /dev/null
+++ b/examples/sync_signal/input.css
@@ -0,0 +1,3 @@
+@tailwind base;
+@tailwind components;
+@tailwind utilities;
\ No newline at end of file
diff --git a/examples/sync_signal/rust-toolchain.toml b/examples/sync_signal/rust-toolchain.toml
new file mode 100644
index 0000000..271800c
--- /dev/null
+++ b/examples/sync_signal/rust-toolchain.toml
@@ -0,0 +1,2 @@
+[toolchain]
+channel = "nightly"
\ No newline at end of file
diff --git a/examples/sync_signal/src/main.rs b/examples/sync_signal/src/main.rs
new file mode 100644
index 0000000..8fdb931
--- /dev/null
+++ b/examples/sync_signal/src/main.rs
@@ -0,0 +1,25 @@
+use leptos::*;
+use leptos_use::docs::demo_or_body;
+use leptos_use::sync_signal;
+
+#[component]
+fn Demo() -> impl IntoView {
+ let (a, set_a) = create_signal(String::new());
+ let (b, set_b) = create_signal(String::new());
+
+ let _ = sync_signal((a, set_a), (b, set_b));
+
+ view! {
+
+
+ }
+}
+
+fn main() {
+ _ = console_log::init_with_level(log::Level::Debug);
+ console_error_panic_hook::set_once();
+
+ mount_to(demo_or_body(), || {
+ view! { }
+ })
+}
diff --git a/examples/sync_signal/style/output.css b/examples/sync_signal/style/output.css
new file mode 100644
index 0000000..ab5191f
--- /dev/null
+++ b/examples/sync_signal/style/output.css
@@ -0,0 +1,289 @@
+[type='text'],[type='email'],[type='url'],[type='password'],[type='number'],[type='date'],[type='datetime-local'],[type='month'],[type='search'],[type='tel'],[type='time'],[type='week'],[multiple],textarea,select {
+ -webkit-appearance: none;
+ -moz-appearance: none;
+ appearance: none;
+ background-color: #fff;
+ border-color: #6b7280;
+ border-width: 1px;
+ border-radius: 0px;
+ padding-top: 0.5rem;
+ padding-right: 0.75rem;
+ padding-bottom: 0.5rem;
+ padding-left: 0.75rem;
+ font-size: 1rem;
+ line-height: 1.5rem;
+ --tw-shadow: 0 0 #0000;
+}
+
+[type='text']:focus, [type='email']:focus, [type='url']:focus, [type='password']:focus, [type='number']:focus, [type='date']:focus, [type='datetime-local']:focus, [type='month']:focus, [type='search']:focus, [type='tel']:focus, [type='time']:focus, [type='week']:focus, [multiple]:focus, textarea:focus, select:focus {
+ outline: 2px solid transparent;
+ outline-offset: 2px;
+ --tw-ring-inset: var(--tw-empty,/*!*/ /*!*/);
+ --tw-ring-offset-width: 0px;
+ --tw-ring-offset-color: #fff;
+ --tw-ring-color: #2563eb;
+ --tw-ring-offset-shadow: var(--tw-ring-inset) 0 0 0 var(--tw-ring-offset-width) var(--tw-ring-offset-color);
+ --tw-ring-shadow: var(--tw-ring-inset) 0 0 0 calc(1px + var(--tw-ring-offset-width)) var(--tw-ring-color);
+ box-shadow: var(--tw-ring-offset-shadow), var(--tw-ring-shadow), var(--tw-shadow);
+ border-color: #2563eb;
+}
+
+input::-moz-placeholder, textarea::-moz-placeholder {
+ color: #6b7280;
+ opacity: 1;
+}
+
+input::placeholder,textarea::placeholder {
+ color: #6b7280;
+ opacity: 1;
+}
+
+::-webkit-datetime-edit-fields-wrapper {
+ padding: 0;
+}
+
+::-webkit-date-and-time-value {
+ min-height: 1.5em;
+}
+
+::-webkit-datetime-edit,::-webkit-datetime-edit-year-field,::-webkit-datetime-edit-month-field,::-webkit-datetime-edit-day-field,::-webkit-datetime-edit-hour-field,::-webkit-datetime-edit-minute-field,::-webkit-datetime-edit-second-field,::-webkit-datetime-edit-millisecond-field,::-webkit-datetime-edit-meridiem-field {
+ padding-top: 0;
+ padding-bottom: 0;
+}
+
+select {
+ background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3e%3cpath stroke='%236b7280' stroke-linecap='round' stroke-linejoin='round' stroke-width='1.5' d='M6 8l4 4 4-4'/%3e%3c/svg%3e");
+ background-position: right 0.5rem center;
+ background-repeat: no-repeat;
+ background-size: 1.5em 1.5em;
+ padding-right: 2.5rem;
+ -webkit-print-color-adjust: exact;
+ print-color-adjust: exact;
+}
+
+[multiple] {
+ background-image: initial;
+ background-position: initial;
+ background-repeat: unset;
+ background-size: initial;
+ padding-right: 0.75rem;
+ -webkit-print-color-adjust: unset;
+ print-color-adjust: unset;
+}
+
+[type='checkbox'],[type='radio'] {
+ -webkit-appearance: none;
+ -moz-appearance: none;
+ appearance: none;
+ padding: 0;
+ -webkit-print-color-adjust: exact;
+ print-color-adjust: exact;
+ display: inline-block;
+ vertical-align: middle;
+ background-origin: border-box;
+ -webkit-user-select: none;
+ -moz-user-select: none;
+ user-select: none;
+ flex-shrink: 0;
+ height: 1rem;
+ width: 1rem;
+ color: #2563eb;
+ background-color: #fff;
+ border-color: #6b7280;
+ border-width: 1px;
+ --tw-shadow: 0 0 #0000;
+}
+
+[type='checkbox'] {
+ border-radius: 0px;
+}
+
+[type='radio'] {
+ border-radius: 100%;
+}
+
+[type='checkbox']:focus,[type='radio']:focus {
+ outline: 2px solid transparent;
+ outline-offset: 2px;
+ --tw-ring-inset: var(--tw-empty,/*!*/ /*!*/);
+ --tw-ring-offset-width: 2px;
+ --tw-ring-offset-color: #fff;
+ --tw-ring-color: #2563eb;
+ --tw-ring-offset-shadow: var(--tw-ring-inset) 0 0 0 var(--tw-ring-offset-width) var(--tw-ring-offset-color);
+ --tw-ring-shadow: var(--tw-ring-inset) 0 0 0 calc(2px + var(--tw-ring-offset-width)) var(--tw-ring-color);
+ box-shadow: var(--tw-ring-offset-shadow), var(--tw-ring-shadow), var(--tw-shadow);
+}
+
+[type='checkbox']:checked,[type='radio']:checked {
+ border-color: transparent;
+ background-color: currentColor;
+ background-size: 100% 100%;
+ background-position: center;
+ background-repeat: no-repeat;
+}
+
+[type='checkbox']:checked {
+ background-image: url("data:image/svg+xml,%3csvg viewBox='0 0 16 16' fill='white' xmlns='http://www.w3.org/2000/svg'%3e%3cpath d='M12.207 4.793a1 1 0 010 1.414l-5 5a1 1 0 01-1.414 0l-2-2a1 1 0 011.414-1.414L6.5 9.086l4.293-4.293a1 1 0 011.414 0z'/%3e%3c/svg%3e");
+}
+
+[type='radio']:checked {
+ background-image: url("data:image/svg+xml,%3csvg viewBox='0 0 16 16' fill='white' xmlns='http://www.w3.org/2000/svg'%3e%3ccircle cx='8' cy='8' r='3'/%3e%3c/svg%3e");
+}
+
+[type='checkbox']:checked:hover,[type='checkbox']:checked:focus,[type='radio']:checked:hover,[type='radio']:checked:focus {
+ border-color: transparent;
+ background-color: currentColor;
+}
+
+[type='checkbox']:indeterminate {
+ background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 16 16'%3e%3cpath stroke='white' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M4 8h8'/%3e%3c/svg%3e");
+ border-color: transparent;
+ background-color: currentColor;
+ background-size: 100% 100%;
+ background-position: center;
+ background-repeat: no-repeat;
+}
+
+[type='checkbox']:indeterminate:hover,[type='checkbox']:indeterminate:focus {
+ border-color: transparent;
+ background-color: currentColor;
+}
+
+[type='file'] {
+ background: unset;
+ border-color: inherit;
+ border-width: 0;
+ border-radius: 0;
+ padding: 0;
+ font-size: unset;
+ line-height: inherit;
+}
+
+[type='file']:focus {
+ outline: 1px solid ButtonText;
+ outline: 1px auto -webkit-focus-ring-color;
+}
+
+*, ::before, ::after {
+ --tw-border-spacing-x: 0;
+ --tw-border-spacing-y: 0;
+ --tw-translate-x: 0;
+ --tw-translate-y: 0;
+ --tw-rotate: 0;
+ --tw-skew-x: 0;
+ --tw-skew-y: 0;
+ --tw-scale-x: 1;
+ --tw-scale-y: 1;
+ --tw-pan-x: ;
+ --tw-pan-y: ;
+ --tw-pinch-zoom: ;
+ --tw-scroll-snap-strictness: proximity;
+ --tw-gradient-from-position: ;
+ --tw-gradient-via-position: ;
+ --tw-gradient-to-position: ;
+ --tw-ordinal: ;
+ --tw-slashed-zero: ;
+ --tw-numeric-figure: ;
+ --tw-numeric-spacing: ;
+ --tw-numeric-fraction: ;
+ --tw-ring-inset: ;
+ --tw-ring-offset-width: 0px;
+ --tw-ring-offset-color: #fff;
+ --tw-ring-color: rgb(59 130 246 / 0.5);
+ --tw-ring-offset-shadow: 0 0 #0000;
+ --tw-ring-shadow: 0 0 #0000;
+ --tw-shadow: 0 0 #0000;
+ --tw-shadow-colored: 0 0 #0000;
+ --tw-blur: ;
+ --tw-brightness: ;
+ --tw-contrast: ;
+ --tw-grayscale: ;
+ --tw-hue-rotate: ;
+ --tw-invert: ;
+ --tw-saturate: ;
+ --tw-sepia: ;
+ --tw-drop-shadow: ;
+ --tw-backdrop-blur: ;
+ --tw-backdrop-brightness: ;
+ --tw-backdrop-contrast: ;
+ --tw-backdrop-grayscale: ;
+ --tw-backdrop-hue-rotate: ;
+ --tw-backdrop-invert: ;
+ --tw-backdrop-opacity: ;
+ --tw-backdrop-saturate: ;
+ --tw-backdrop-sepia: ;
+}
+
+::backdrop {
+ --tw-border-spacing-x: 0;
+ --tw-border-spacing-y: 0;
+ --tw-translate-x: 0;
+ --tw-translate-y: 0;
+ --tw-rotate: 0;
+ --tw-skew-x: 0;
+ --tw-skew-y: 0;
+ --tw-scale-x: 1;
+ --tw-scale-y: 1;
+ --tw-pan-x: ;
+ --tw-pan-y: ;
+ --tw-pinch-zoom: ;
+ --tw-scroll-snap-strictness: proximity;
+ --tw-gradient-from-position: ;
+ --tw-gradient-via-position: ;
+ --tw-gradient-to-position: ;
+ --tw-ordinal: ;
+ --tw-slashed-zero: ;
+ --tw-numeric-figure: ;
+ --tw-numeric-spacing: ;
+ --tw-numeric-fraction: ;
+ --tw-ring-inset: ;
+ --tw-ring-offset-width: 0px;
+ --tw-ring-offset-color: #fff;
+ --tw-ring-color: rgb(59 130 246 / 0.5);
+ --tw-ring-offset-shadow: 0 0 #0000;
+ --tw-ring-shadow: 0 0 #0000;
+ --tw-shadow: 0 0 #0000;
+ --tw-shadow-colored: 0 0 #0000;
+ --tw-blur: ;
+ --tw-brightness: ;
+ --tw-contrast: ;
+ --tw-grayscale: ;
+ --tw-hue-rotate: ;
+ --tw-invert: ;
+ --tw-saturate: ;
+ --tw-sepia: ;
+ --tw-drop-shadow: ;
+ --tw-backdrop-blur: ;
+ --tw-backdrop-brightness: ;
+ --tw-backdrop-contrast: ;
+ --tw-backdrop-grayscale: ;
+ --tw-backdrop-hue-rotate: ;
+ --tw-backdrop-invert: ;
+ --tw-backdrop-opacity: ;
+ --tw-backdrop-saturate: ;
+ --tw-backdrop-sepia: ;
+}
+
+.block {
+ display: block;
+}
+
+.text-\[--brand-color\] {
+ color: var(--brand-color);
+}
+
+.text-green-600 {
+ --tw-text-opacity: 1;
+ color: rgb(22 163 74 / var(--tw-text-opacity));
+}
+
+.opacity-75 {
+ opacity: 0.75;
+}
+
+@media (prefers-color-scheme: dark) {
+ .dark\:text-green-500 {
+ --tw-text-opacity: 1;
+ color: rgb(34 197 94 / var(--tw-text-opacity));
+ }
+}
\ No newline at end of file
diff --git a/examples/sync_signal/tailwind.config.js b/examples/sync_signal/tailwind.config.js
new file mode 100644
index 0000000..bc09f5e
--- /dev/null
+++ b/examples/sync_signal/tailwind.config.js
@@ -0,0 +1,15 @@
+/** @type {import('tailwindcss').Config} */
+module.exports = {
+ content: {
+ files: ["*.html", "./src/**/*.rs", "../../src/docs/**/*.rs"],
+ },
+ theme: {
+ extend: {},
+ },
+ corePlugins: {
+ preflight: false,
+ },
+ plugins: [
+ require('@tailwindcss/forms'),
+ ],
+}
\ No newline at end of file
diff --git a/src/core/mod.rs b/src/core/mod.rs
index 577cf7f..3fe5ca3 100644
--- a/src/core/mod.rs
+++ b/src/core/mod.rs
@@ -10,6 +10,7 @@ mod size;
mod ssr_safe_method;
mod storage;
pub(crate) mod url;
+mod use_rw_signal;
pub use connection_ready_state::*;
pub(crate) use datetime::*;
@@ -22,3 +23,4 @@ pub use position::*;
pub use size::*;
pub(crate) use ssr_safe_method::*;
pub use storage::*;
+pub use use_rw_signal::*;
diff --git a/src/core/use_rw_signal.rs b/src/core/use_rw_signal.rs
new file mode 100644
index 0000000..ba19a44
--- /dev/null
+++ b/src/core/use_rw_signal.rs
@@ -0,0 +1,171 @@
+use leptos::*;
+
+pub enum UseRwSignal {
+ Separate(Signal, WriteSignal),
+ Combined(RwSignal),
+}
+
+impl From> for UseRwSignal {
+ fn from(s: RwSignal) -> Self {
+ Self::Combined(s)
+ }
+}
+
+impl From<(RS, WriteSignal)> for UseRwSignal
+where
+ RS: Into>,
+{
+ fn from(s: (RS, WriteSignal)) -> Self {
+ Self::Separate(s.0.into(), s.1)
+ }
+}
+
+impl Default for UseRwSignal
+where
+ T: Default,
+{
+ fn default() -> Self {
+ Self::Combined(Default::default())
+ }
+}
+
+impl Clone for UseRwSignal {
+ fn clone(&self) -> Self {
+ match self {
+ Self::Separate(s, w) => Self::Separate(s.clone(), w.clone()),
+ Self::Combined(s) => Self::Combined(s.clone()),
+ }
+ }
+}
+
+impl Copy for UseRwSignal {}
+
+impl SignalGet for UseRwSignal
+where
+ T: Clone,
+{
+ type Value = T;
+
+ fn get(&self) -> T {
+ match self {
+ Self::Separate(s, _) => s.get(),
+ Self::Combined(s) => s.get(),
+ }
+ }
+
+ fn try_get(&self) -> Option {
+ match self {
+ Self::Separate(s, _) => s.try_get(),
+ Self::Combined(s) => s.try_get(),
+ }
+ }
+}
+
+impl SignalGetUntracked for UseRwSignal
+where
+ T: Clone,
+{
+ type Value = T;
+
+ fn get_untracked(&self) -> T {
+ match self {
+ Self::Separate(s, _) => s.get_untracked(),
+ Self::Combined(s) => s.get_untracked(),
+ }
+ }
+
+ fn try_get_untracked(&self) -> Option {
+ match self {
+ Self::Separate(s, _) => s.try_get_untracked(),
+ Self::Combined(s) => s.try_get_untracked(),
+ }
+ }
+}
+
+impl SignalWith for UseRwSignal {
+ type Value = T;
+
+ fn with(&self, f: impl FnOnce(&T) -> R) -> R {
+ match self {
+ Self::Separate(s, _) => s.with(f),
+ Self::Combined(s) => s.with(f),
+ }
+ }
+
+ fn try_with(&self, f: impl FnOnce(&T) -> R) -> Option {
+ match self {
+ Self::Separate(s, _) => s.try_with(f),
+ Self::Combined(s) => s.try_with(f),
+ }
+ }
+}
+
+impl SignalWithUntracked for UseRwSignal {
+ type Value = T;
+
+ fn with_untracked(&self, f: impl FnOnce(&T) -> R) -> R {
+ match self {
+ Self::Separate(s, _) => s.with_untracked(f),
+ Self::Combined(s) => s.with_untracked(f),
+ }
+ }
+
+ fn try_with_untracked(&self, f: impl FnOnce(&T) -> R) -> Option {
+ match self {
+ Self::Separate(s, _) => s.try_with_untracked(f),
+ Self::Combined(s) => s.try_with_untracked(f),
+ }
+ }
+}
+
+impl SignalSet for UseRwSignal {
+ type Value = T;
+
+ fn set(&self, new_value: T) {
+ match *self {
+ Self::Separate(_, s) => s.set(new_value),
+ Self::Combined(s) => s.set(new_value),
+ }
+ }
+
+ fn try_set(&self, new_value: T) -> Option {
+ match *self {
+ Self::Separate(_, s) => s.try_set(new_value),
+ Self::Combined(s) => s.try_set(new_value),
+ }
+ }
+}
+
+impl SignalSetUntracked for UseRwSignal {
+ fn set_untracked(&self, new_value: T) {
+ match self {
+ Self::Separate(_, s) => s.set_untracked(new_value),
+ Self::Combined(s) => s.set_untracked(new_value),
+ }
+ }
+
+ fn try_set_untracked(&self, new_value: T) -> Option {
+ match self {
+ Self::Separate(_, s) => s.try_set_untracked(new_value),
+ Self::Combined(s) => s.try_set_untracked(new_value),
+ }
+ }
+}
+
+impl SignalUpdate for UseRwSignal {
+ type Value = T;
+
+ fn update(&self, f: impl FnOnce(&mut T)) {
+ match self {
+ Self::Separate(_, s) => s.update(f),
+ Self::Combined(s) => s.update(f),
+ }
+ }
+
+ fn try_update(&self, f: impl FnOnce(&mut T) -> O) -> Option {
+ match self {
+ Self::Separate(_, s) => s.try_update(f),
+ Self::Combined(s) => s.try_update(f),
+ }
+ }
+}
diff --git a/src/lib.rs b/src/lib.rs
index 1672844..58dc229 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -24,6 +24,7 @@ mod is_none;
mod is_ok;
mod is_some;
mod on_click_outside;
+mod sync_signal;
mod signal_debounced;
mod signal_throttled;
mod use_active_element;
@@ -88,6 +89,7 @@ pub use is_none::*;
pub use is_ok::*;
pub use is_some::*;
pub use on_click_outside::*;
+pub use sync_signal::*;
pub use signal_debounced::*;
pub use signal_throttled::*;
pub use use_active_element::*;
diff --git a/src/sync_signal.rs b/src/sync_signal.rs
new file mode 100644
index 0000000..d94da74
--- /dev/null
+++ b/src/sync_signal.rs
@@ -0,0 +1,258 @@
+use crate::core::UseRwSignal;
+use default_struct_builder::DefaultBuilder;
+use leptos::*;
+use std::fmt::Debug;
+use std::rc::Rc;
+
+/// Two-way Signals synchronization.
+///
+/// > Note: Please consider first if you can achieve your goals with the
+/// > ["Good Options" described in the Leptos book](https://book.leptos.dev/reactivity/working_with_signals.html#making-signals-depend-on-each-other)
+/// > firstly. Only if you really have to, use this function. This is in effect the
+/// > ["If you really must..."](https://book.leptos.dev/reactivity/working_with_signals.html#if-you-really-must).
+///
+/// ## Demo
+///
+/// [Link to Demo](https://github.com/Synphonyte/leptos-use/tree/main/examples/sync_signal)
+///
+/// ## Usage
+///
+/// ```
+/// # use leptos::*;
+/// # use leptos_use::sync_signal;
+/// #
+/// # #[component]
+/// # fn Demo() -> impl IntoView {
+/// let (a, set_a) = create_signal(1);
+/// let (b, set_b) = create_signal(2);
+///
+/// let stop = sync_signal((a, set_a), (b, set_b));
+///
+/// logging::log!("a: {}, b: {}", a.get(), b.get()); // a: 1, b: 1
+///
+/// set_b.set(3);
+///
+/// logging::log!("a: {}, b: {}", a.get(), b.get()); // a: 3, b: 3
+///
+/// set_a.set(4);
+///
+/// logging::log!("a: {}, b: {}", a.get(), b.get()); // a: 4, b: 4
+/// #
+/// # view! { }
+/// # }
+/// ```
+///
+/// ### `RwSignal`
+///
+/// You can mix and match `RwSignal`s and `Signal`-`WriteSignal` pairs.
+///
+/// ```
+/// # use leptos::*;
+/// # use leptos_use::sync_signal;
+/// #
+/// # #[component]
+/// # fn Demo() -> impl IntoView {
+/// let (a, set_a) = create_signal(1);
+/// let (b, set_b) = create_signal(2);
+/// let c_rw = create_rw_signal(3);
+/// let d_rw = create_rw_signal(4);
+///
+/// sync_signal((a, set_a), c_rw);
+/// sync_signal(d_rw, (b, set_b));
+/// sync_signal(c_rw, d_rw);
+///
+/// #
+/// # view! { }
+/// # }
+/// ```
+///
+/// ### One directional
+///
+/// You can synchronize a signal only from left to right or right to left.
+///
+/// ```
+/// # use leptos::*;
+/// # use leptos_use::{sync_signal_with_options, SyncSignalOptions, SyncDirection};
+/// #
+/// # #[component]
+/// # fn Demo() -> impl IntoView {
+/// let (a, set_a) = create_signal(1);
+/// let (b, set_b) = create_signal(2);
+///
+/// let stop = sync_signal_with_options(
+/// (a, set_a),
+/// (b, set_b),
+/// SyncSignalOptions::default().direction(SyncDirection::LeftToRight)
+/// );
+///
+/// set_b.set(3); // doesn't sync
+///
+/// logging::log!("a: {}, b: {}", a.get(), b.get()); // a: 1, b: 3
+///
+/// set_a.set(4);
+///
+/// logging::log!("a: {}, b: {}", a.get(), b.get()); // a: 4, b: 4
+/// #
+/// # view! { }
+/// # }
+/// ```
+///
+/// ### Custom Transform
+///
+/// You can optionally provide custom transforms between the two signals.
+/// ```
+/// # use leptos::*;
+/// # use leptos_use::{sync_signal_with_options, SyncSignalOptions};
+/// #
+/// # #[component]
+/// # fn Demo() -> impl IntoView {
+/// let (a, set_a) = create_signal(10);
+/// let (b, set_b) = create_signal(2);
+///
+/// let stop = sync_signal_with_options(
+/// (a, set_a),
+/// (b, set_b),
+/// SyncSignalOptions::default()
+/// .transform_ltr(|left| *left * 2)
+/// .transform_rtl(|right| *right / 2)
+/// );
+///
+/// logging::log!("a: {}, b: {}", a.get(), b.get()); // a: 10, b: 20
+///
+/// set_b.set(30);
+///
+/// logging::log!("a: {}, b: {}", a.get(), b.get()); // a: 15, b: 30
+/// #
+/// # view! { }
+/// # }
+/// ```
+pub fn sync_signal(
+ left: impl Into>,
+ right: impl Into>,
+) -> impl Fn() + Clone
+where
+ T: Clone + PartialEq + 'static,
+{
+ sync_signal_with_options(left, right, SyncSignalOptions::default())
+}
+
+/// Version of [`sync_signal`] that takes a `SyncSignalOptions`. See [`sync_signal`] for how to use.
+pub fn sync_signal_with_options(
+ left: impl Into>,
+ right: impl Into>,
+ options: SyncSignalOptions,
+) -> impl Fn() + Clone
+where
+ L: Clone + PartialEq + 'static,
+ R: Clone + PartialEq + 'static,
+{
+ let SyncSignalOptions {
+ immediate,
+ direction,
+ transform_ltr,
+ transform_rtl,
+ } = options;
+
+ let left = left.into();
+ let right = right.into();
+
+ let mut stop_watch_left = None;
+ let mut stop_watch_right = None;
+
+ if matches!(direction, SyncDirection::Both | SyncDirection::LeftToRight) {
+ stop_watch_left = Some(watch(
+ move || left.get(),
+ move |new_value, _, _| {
+ let new_value = (*transform_ltr)(new_value);
+
+ if right.with_untracked(|right| right != &new_value) {
+ right.update(|right| *right = new_value);
+ }
+ },
+ immediate,
+ ));
+ }
+
+ if matches!(direction, SyncDirection::Both | SyncDirection::RightToLeft) {
+ stop_watch_right = Some(watch(
+ move || right.get(),
+ move |new_value, _, _| {
+ let new_value = (*transform_rtl)(new_value);
+
+ if left.with_untracked(|left| left != &new_value) {
+ left.update(|left| *left = new_value);
+ }
+ },
+ immediate,
+ ));
+ }
+
+ move || {
+ if let Some(stop_watch_left) = &stop_watch_left {
+ stop_watch_left();
+ }
+ if let Some(stop_watch_right) = &stop_watch_right {
+ stop_watch_right();
+ }
+ }
+}
+
+/// Direction of syncing.
+pub enum SyncDirection {
+ LeftToRight,
+ RightToLeft,
+ Both,
+}
+
+/// Options for [`sync_signal_with_options`].
+#[derive(DefaultBuilder)]
+pub struct SyncSignalOptions {
+ /// If `true`, the signals will be immediately synced when this function is called.
+ /// If `false`, a signal is only updated when the other signal's value changes.
+ /// Defaults to `true`.
+ immediate: bool,
+
+ /// Direction of syncing. Defaults to `SyncDirection::Both`.
+ direction: SyncDirection,
+
+ /// Transforms the left signal into the right signal.
+ /// Defaults to identity.
+ #[builder(skip)]
+ transform_ltr: Rc R>,
+
+ /// Transforms the right signal into the left signal.
+ /// Defaults to identity.
+ #[builder(skip)]
+ transform_rtl: Rc L>,
+}
+
+impl SyncSignalOptions {
+ /// Transforms the left signal into the right signal.
+ /// Defaults to identity.
+ pub fn transform_ltr(self, transform_ltr: impl Fn(&L) -> R + 'static) -> Self {
+ Self {
+ transform_ltr: Rc::new(transform_ltr),
+ ..self
+ }
+ }
+
+ /// Transforms the right signal into the left signal.
+ /// Defaults to identity.
+ pub fn transform_rtl(self, transform_rtl: impl Fn(&R) -> L + 'static) -> Self {
+ Self {
+ transform_rtl: Rc::new(transform_rtl),
+ ..self
+ }
+ }
+}
+
+impl Default for SyncSignalOptions {
+ fn default() -> Self {
+ Self {
+ immediate: true,
+ direction: SyncDirection::Both,
+ transform_ltr: Rc::new(|x| x.clone()),
+ transform_rtl: Rc::new(|x| x.clone()),
+ }
+ }
+}