Prompt
When implementing algorithms, carefully evaluate trade-offs between built-in methods, custom implementations, and different algorithmic approaches. Consider factors like browser compatibility, performance characteristics, maintainability, and edge case handling.
Key considerations:
- Compatibility vs. Performance: Built-in methods may not be available in all target environments. For example,
Array.findLast()requires Safari 15.4+, necessitating custom implementations for broader compatibility. - Data Structure Handling: Choose appropriate data structures based on usage patterns. For FormData processing, always using arrays simplifies logic despite slight overhead, while conditional arrays add complexity but optimize common cases.
- String Processing Approaches: Consider regex vs. conditional logic based on complexity and performance needs. Regex may seem simpler but can introduce escaping issues and compilation overhead.
Example from the discussions:
// Custom implementation for compatibility
export function findLast<T>(
array: ReadonlyArray<T>,
predicate: (item: T) => boolean,
): T | undefined {
for (let i = array.length - 1; i >= 0; i--) {
const item = array[i]!
if (predicate(item)) return item
}
return undefined
}
// vs. built-in (when available)
array.findLast(predicate)
Document the reasoning behind algorithmic choices to help future maintainers understand the trade-offs made.