Adding valueChanged function to replace onValueChanged method on redu…

…ctions
soxtoby · Oct 27, 2023 · c7e9e97 · c7e9e97
1 parent 3fbff91
commit c7e9e97
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Showing 6 changed files with 17 additions and 11 deletions.
diff --git a/packages/event-reduce-react/package.json b/packages/event-reduce-react/package.json
@@ -1,7 +1,7 @@
 {
   "name": "event-reduce-react",
   "description": "React integration for event-reduce: state management based on reducing observable events into state",
-  "version": "0.5.1",
+  "version": "0.5.2",
   "author": "Simon Oxtoby",
   "homepage": "https://github.com/soxtoby/event-reduce",
   "repository": {

diff --git a/packages/event-reduce/package.json b/packages/event-reduce/package.json
@@ -1,7 +1,7 @@
 {
   "name": "event-reduce",
   "description": "State management based on reducing observable events into state",
-  "version": "0.5.1",
+  "version": "0.5.2",
   "author": "Simon Oxtoby",
   "homepage": "https://github.com/soxtoby/event-reduce",
   "repository": {

diff --git a/packages/event-reduce/src/index.ts b/packages/event-reduce/src/index.ts
@@ -4,7 +4,7 @@ export { AsyncError, AsyncResult, AsyncStart, IAsyncEvent, IAsyncObservables, IE
 export { enableLogging } from "./logging";
 export { derived, events, extend, model, reduced, state } from "./models";
 export { IObservable, IObserver, Observable, Observe, allSources, merge } from "./observable";
-export { IObservableValue } from "./observableValue";
+export { IObservableValue, valueChanged } from "./observableValue";
 export { IBoundReduction, IReduction, reduce } from "./reduction";
 export { State, getState, setState } from "./state";
 export { ISubject, Subject } from "./subject";

diff --git a/packages/event-reduce/src/observableValue.ts b/packages/event-reduce/src/observableValue.ts
@@ -123,6 +123,14 @@ export function startTrackingScope(): Unsubscribe {
     }
 }
 
+/** Allows subscribing to the changes of the specified observable value. */
+export function valueChanged<T>(observableValue: T) {
+    let observable = getUnderlyingObservable(observableValue);
+    if (observable)
+        return observable.values;
+    throw new ValueIsNotObservableError(observableValue);
+}
+
 export function getUnderlyingObservable<T>(value: T): ObservableValue<T> | undefined {
     let lastAccessed = consumeLastAccessed();
     if (lastAccessed && withInnerTrackingScope(() => lastAccessed!.value) == value)

diff --git a/packages/event-reduce/src/reduction.ts b/packages/event-reduce/src/reduction.ts
@@ -1,6 +1,6 @@
 import { log, sourceTree } from "./logging";
 import { IObservable, allSources, isObservable } from "./observable";
-import { IObservableValue, ObservableValue, ValueIsNotObservableError, getUnderlyingObservable, protectAgainstAccessingValueWithCommonSource } from "./observableValue";
+import { IObservableValue, ObservableValue, ValueIsNotObservableError, getUnderlyingObservable, protectAgainstAccessingValueWithCommonSource, valueChanged } from "./observableValue";
 import { State, setState } from "./state";
 import { Subject } from "./subject";
 import { Unsubscribe } from "./types";
@@ -18,6 +18,7 @@ type Reducer<TValue, TEvent> = (previous: TValue, eventValue: TEvent) => TValue;
 
 export interface IReduction<T> extends IObservableValue<T> {
     on<TEvent>(observable: IObservable<TEvent>, reduce: Reducer<T, TEvent>): this;
+    /** @deprecated use valueChanged function instead */
     onValueChanged<TValue>(observableVaue: TValue, reduce: Reducer<T, TValue>): this;
     onRestore(reduce: Reducer<T, State<T>>): this;
 }
@@ -72,10 +73,7 @@ export class Reduction<T> extends ObservableValue<T> implements IReduction<T> {
     }
 
     onValueChanged<TValue>(observableValue: TValue, reduce: Reducer<T, TValue>) {
-        let observable = getUnderlyingObservable(observableValue);
-        if (observable)
-            return this.on(observable.values, reduce);
-        throw new ValueIsNotObservableError(observableValue);
+        return this.on(valueChanged(observableValue), reduce);
     }
 
     onRestore(reduce: Reducer<T, State<T>>): this {

diff --git a/tests/ModelTests.ts b/tests/ModelTests.ts
@@ -1,5 +1,5 @@
 import { asyncEvent, derive, derived, event, events, extend, model, reduce, reduced } from "event-reduce";
-import { AccessedValueWithCommonSourceError } from "event-reduce/lib/observableValue";
+import { AccessedValueWithCommonSourceError, valueChanged } from "event-reduce/lib/observableValue";
 import { describe, it, test, then, when } from "wattle";
 
 describe("models", function () {
@@ -15,7 +15,7 @@ describe("models", function () {
 
         @reduced
         dependentProperty = reduce(1)
-            .onValueChanged(this.property, (_, p) => p)
+            .on(valueChanged(this.property), (_, p) => p)
             .value;
 
         @derived
@@ -28,7 +28,7 @@ describe("models", function () {
 
         @reduced
         basedOnDerivedProperty = reduce(0)
-            .onValueChanged(this.derivedProperty, (_, d) => d)
+            .on(valueChanged(this.derivedProperty), (_, d) => d)
             .value;
     }
     let testModel = new TestModel();