Algorithms & Logic
The efficiency of your business logic directly impacts battery life and responsiveness.
Complexity Analysis
- Big O Awareness: Understand the cost of your operations. Avoid O(n²) or higher on the main thread for datasets larger than a few hundred items.
- Data Structure Selection:
Map: Fast key-based lookups.Set: Fast unique item management.List: Fast indexing and sequential access.LinkedHashSet/Map: Preserves insertion order while providing fast lookups.
Logic Patterns
- Debouncing: Delay execution until a user stops interacting (e.g., search-as-you-type).
- Throttling: Limit execution to at most once every interval (e.g., scrolling events).
- Memoization: Cache the results of expensive pure functions based on their arguments. Use
package:memoizeor custom implementations.
Search & Sort
- Binary Search: Use for sorted lists to transform O(n) searches into O(log n).
- Efficient Sorting: Use Dart’s built-in
list.sort(), which uses highly optimized algorithms. Provide targetedComparableimplementations for custom objects.
Business Logic Organization
- Pure Functions: Keep business logic in pure, testable functions outside of UI classes.
- Fail Fast: Use guard clauses to handle edge cases and invalid states early.
- Validation Logic: Keep complex validation in a separate domain layer, reusable across different screens.