Dennis Hundertmark
38 lines
964 B
Markdown
38 lines
964 B
Markdown
# Angular Ngrx Best Practices
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> Use with the core `angular-best-practices` skill.
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---
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## 1. NgRx State Management
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**Impact: HIGH** (Global state)
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### 1.1 Keep Reducers Pure
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**Impact: HIGH** (Predictable state, testable, time-travel debugging)
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Reducers must be pure functions: no side effects, no HTTP calls, no subscriptions. Only compute new state from action and current state. Move side effects to Effects.
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**Example:**
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```typescript
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on(UsersActions.load, (state) => ({ ...state, loading: true }));
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// HTTP call goes in UsersEffects
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```
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### 1.2 Use Feature Selectors
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**Impact: MEDIUM** (Memoized selection, better performance)
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Use `createFeatureSelector` and `createSelector` for memoized state selection. Selectors only recompute when their inputs change.
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**Example:**
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```typescript
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const selectCounterState = createFeatureSelector<CounterState>('counter');
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export const selectCount = createSelector(selectCounterState, (s) => s.count);
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```
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---
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