Fix TODO example

mstniy · Dec 3, 2023 · 2fe0028 · 2fe0028
1 parent f9e254b
commit 2fe0028
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Showing 2 changed files with 7 additions and 7 deletions.
diff --git a/example/todo.dart b/example/todo.dart
@@ -57,8 +57,9 @@ void main() async {
         uiUpdate.react((t) {
           b[t.item1] = t.item2;
         }, null);
+        final id = largestId.use;
         uiCreate.react((t) {
-          b[largestId.use] = t;
+          b[id] = t;
         }, null);
       },
     );

diff --git a/lib/src/computed.dart b/lib/src/computed.dart
@@ -129,6 +129,7 @@ class ComputedImpl<T> with Computed<T> {
   bool get _novalue => _lastResult == null;
   _ValueOrException<T>? _lastResult;
   _ValueOrException<T>? _prevResult;
+  T? _initialPrev;
   Map<ComputedImpl, _MemoizedValueOrException>?
       _lastResultfulUpstreamComputations;
   var _lastUpstreamComputations = <ComputedImpl, _MemoizedValueOrException>{};
@@ -148,8 +149,8 @@ class ComputedImpl<T> with Computed<T> {
   T get prev {
     final caller = GlobalCtx.currentComputation;
     if (caller == this) {
-      if (_prevResult == null) throw NoValueException();
-      return _prevResult!.value;
+      if (_prevResult == null && _initialPrev == null) throw NoValueException();
+      return (_prevResult?.value ?? _initialPrev)!;
     } else {
       if (caller._lastResult == null) throw NoValueException();
       final mvoe = caller._lastResultfulUpstreamComputations![this];
@@ -167,10 +168,8 @@ class ComputedImpl<T> with Computed<T> {
 
   static ComputedImpl<T> withPrev<T>(T Function(T prev) f, T initialPrev) {
     late ComputedImpl<T> c;
-    c = ComputedImpl<T>(() {
-      c._prevResult ??= _ValueOrException.value(initialPrev);
-      return f(c._prevResult!.value);
-    });
+    c = ComputedImpl<T>(() => f(c._prevResult?.value ?? initialPrev));
+    c._initialPrev = initialPrev;
 
     return c;
   }