rename get update to DerivedRw (#697)

Author: jrmoulton

Diff for: examples/timer/src/main.rs

@@ -3,7 +3,7 @@ use std::time::{Duration, Instant};
 use floem::{
     action::exec_after,
     reactive::{
-        create_effect, create_get_update, create_rw_signal, SignalGet, SignalTrack, SignalUpdate,
+        create_effect, create_rw_signal, DerivedRwSignal, SignalGet, SignalTrack, SignalUpdate,
     },
     unit::{Pct, UnitExt},
     views::{button, container, label, slider, stack, text, v_stack, Decorators},
@@ -47,7 +47,7 @@ fn app_view() -> impl IntoView {
         });
     });
 
-    let progress = create_get_update(
+    let progress = DerivedRwSignal::new(
         target_duration,
         move |val| Pct(elapsed_time.get().as_secs_f64() / val.0 * 100.),
         |val| *val,

Diff for: examples/tokio-timer/src/main.rs

@@ -2,7 +2,7 @@ use std::time::Duration;
 
 use floem::ext_event::create_signal_from_stream;
 use floem::prelude::*;
-use floem::reactive::create_get_update;
+use floem::reactive::DerivedRwSignal;
 use floem::unit::Pct;
 use tokio::runtime::Runtime;
 use tokio::time::Instant;
@@ -41,7 +41,7 @@ fn app_view() -> impl IntoView {
         )
     });
 
-    let progress = create_get_update(
+    let progress = DerivedRwSignal::new(
         target_duration,
         move |val| Pct(elapsed_time().as_secs_f64() / val.0 * 100.),
         |val| *val,

Diff for: examples/widget-gallery/src/slider.rs

@@ -1,5 +1,5 @@
 use floem::{
-    reactive::{create_get_update, create_rw_signal, SignalGet},
+    reactive::{create_rw_signal, DerivedRwSignal, SignalGet},
     unit::UnitExt,
     views::{label, slider, stack, text_input, Decorators},
     IntoView,
@@ -9,7 +9,7 @@ use crate::form::{self, form_item};
 
 pub fn slider_view() -> impl IntoView {
     let input = create_rw_signal(String::from("50"));
-    let slider_state = create_get_update(
+    let slider_state = DerivedRwSignal::new(
         input,
         |val| val.parse::<f64>().unwrap_or_default().pct(),
         |val| val.0.to_string(),

Diff for: reactive/src/get_update_fn.rs renamed to reactive/src/derived.rs

@@ -2,23 +2,28 @@ use std::marker::PhantomData;
 
 use crate::{read::SignalTrack, RwSignal, SignalGet, SignalUpdate, SignalWith};
 
-pub struct GetUpdateFn<T, O, GF: Fn(&T) -> O + Clone + 'static, UF: Fn(&O) -> T + 'static> {
+/// A signal that is derived from an [RwSignal](super::RwSignal) but lets you specify getters and setters for the signal.
+///
+/// This is useful when you want a single state variable and don't want to use effects to synchronize multiple signals.
+///
+/// This is also useful when you want a derived signal that implements the [SignalGet], [SignalWith], etc. traits.
+pub struct DerivedRwSignal<T, O, GF: Fn(&T) -> O + Clone + 'static, UF: Fn(&O) -> T + 'static> {
     signal: RwSignal<T>,
     getter: RwSignal<Box<GF>>,
     setter: RwSignal<Box<UF>>,
     ty: PhantomData<T>,
 }
 
-impl<T, O, GF: Fn(&T) -> O + Copy, UF: Fn(&O) -> T + Copy> Clone for GetUpdateFn<T, O, GF, UF> {
+impl<T, O, GF: Fn(&T) -> O + Copy, UF: Fn(&O) -> T + Copy> Clone for DerivedRwSignal<T, O, GF, UF> {
     fn clone(&self) -> Self {
         *self
     }
 }
 
-impl<T, O, GF: Fn(&T) -> O + Copy, UF: Fn(&O) -> T + Copy> Copy for GetUpdateFn<T, O, GF, UF> {}
+impl<T, O, GF: Fn(&T) -> O + Copy, UF: Fn(&O) -> T + Copy> Copy for DerivedRwSignal<T, O, GF, UF> {}
 
 impl<T: Clone + 'static, O: Clone, GF: Fn(&T) -> O + Copy, UF: Fn(&O) -> T + Copy> SignalGet<O>
-    for GetUpdateFn<T, O, GF, UF>
+    for DerivedRwSignal<T, O, GF, UF>
 {
     fn id(&self) -> crate::id::Id {
         self.signal.id
@@ -48,7 +53,7 @@ impl<T: Clone + 'static, O: Clone, GF: Fn(&T) -> O + Copy, UF: Fn(&O) -> T + Cop
 }
 
 impl<T: Clone + 'static, O: Clone, GF: Fn(&T) -> O + Copy, UF: Fn(&O) -> T + Copy> SignalWith<O>
-    for GetUpdateFn<T, O, GF, UF>
+    for DerivedRwSignal<T, O, GF, UF>
 {
     fn id(&self) -> crate::id::Id {
         self.signal.id
@@ -99,7 +104,7 @@ impl<T: Clone + 'static, O: Clone, GF: Fn(&T) -> O + Copy, UF: Fn(&O) -> T + Cop
 }
 
 impl<T: Clone + 'static, O: Clone, GF: Fn(&T) -> O + Copy, UF: Fn(&O) -> T + Copy> SignalTrack<O>
-    for GetUpdateFn<T, O, GF, UF>
+    for DerivedRwSignal<T, O, GF, UF>
 {
     fn id(&self) -> crate::id::Id {
         self.signal.id
@@ -116,7 +121,7 @@ impl<T: Clone + 'static, O: Clone, GF: Fn(&T) -> O + Copy, UF: Fn(&O) -> T + Cop
 }
 
 impl<T: 'static, O, GF: Fn(&T) -> O + Copy, UF: Fn(&O) -> T + Copy> SignalUpdate<O>
-    for GetUpdateFn<T, O, GF, UF>
+    for DerivedRwSignal<T, O, GF, UF>
 {
     fn id(&self) -> crate::id::Id {
         self.signal.id
@@ -168,19 +173,35 @@ impl<T: 'static, O, GF: Fn(&T) -> O + Copy, UF: Fn(&O) -> T + Copy> SignalUpdate
         })
     }
 }
+impl<T, O, GF, UF> DerivedRwSignal<T, O, GF, UF>
+where
+    GF: Fn(&T) -> O + Clone + 'static,
+    UF: Fn(&O) -> T + 'static,
+{
+    pub fn new(signal: RwSignal<T>, getter: GF, setter: UF) -> Self {
+        let getter = RwSignal::new(Box::new(getter));
+        let setter = RwSignal::new(Box::new(setter));
+        DerivedRwSignal {
+            signal,
+            getter,
+            setter,
+            ty: PhantomData,
+        }
+    }
+}
 
-pub fn create_get_update<T, O, GF, UF>(
+pub fn create_derived_rw_signal<T, O, GF, UF>(
     signal: RwSignal<T>,
     getter: GF,
     setter: UF,
-) -> GetUpdateFn<T, O, GF, UF>
+) -> DerivedRwSignal<T, O, GF, UF>
 where
     GF: Fn(&T) -> O + Clone + 'static,
     UF: Fn(&O) -> T + 'static,
 {
     let getter = RwSignal::new(Box::new(getter));
     let setter = RwSignal::new(Box::new(setter));
-    GetUpdateFn {
+    DerivedRwSignal {
         signal,
         getter,
         setter,

Diff for: reactive/src/lib.rs

@@ -6,8 +6,8 @@
 
 mod base;
 mod context;
+mod derived;
 mod effect;
-mod get_update_fn;
 mod id;
 mod impls;
 mod memo;
@@ -20,8 +20,8 @@ mod write;
 
 pub use base::{create_base_signal, BaseSignal};
 pub use context::{provide_context, use_context};
+pub use derived::{create_derived_rw_signal, DerivedRwSignal};
 pub use effect::{batch, create_effect, create_stateful_updater, create_updater, untrack};
-pub use get_update_fn::{create_get_update, GetUpdateFn};
 pub use memo::{create_memo, Memo};
 pub use read::{ReadSignalValue, SignalGet, SignalRead, SignalTrack, SignalWith};
 pub use scope::{as_child_of_current_scope, with_scope, Scope};