Understanding the Selector Pattern and Memoization in ngrx
summary
Explains how the Selector Pattern turns raw state into derived views with concrete code: builds a counter app with increment/decrement/reset (payload-driven reset), wires actions and reducers, and uses the Select API to push values to presentational components. Shows a meta-reducer for multiple instances that routes actions by target id so many counters share one reducer. Demonstrates that ngrx uses memoization cache slot limitation and that replacing selector memoization with an external lib yields large speedups when filtering big arrays.
AI-written summary · about
chapters (7)
- 0:00Introduction and speaker background
- 5:01Fundamentals of ngrx
- 14:10Counter example setup
- 26:46Reducers and multiple counters
- 30:46Understanding selectors
- 38:15Memoization in ngrx
- 40:44Resources and conclusion
related talks
18mBuilding Sub States w/ NgRx Selectors
33mAdvanced State Management using ngrx v5
19mNgRx Selectors: How to stop worrying about your Store structure
36mReact + Redux: Performance & Scalability
22mState Management Techniques and Family Therapy
22mThe Secret Sauce of State Management
32mLevel up your NgRx game
35mAdvanced NgRx Techniques