ReadonlypropertiesinPHP8.2canonlybeassignedonceintheconstructororatdeclarationandcannotbemodifiedafterward,enforcingimmutabilityatthelanguagelevel.2.Toachievedeepimmutability,wrapmutabletypeslikearraysinArrayObjectorusecustomimmutablecollectionssucha

Go's switch statement will not be executed throughout the process by default and will automatically exit after matching the first condition. 1. Switch starts with a keyword and can carry one or no value; 2. Case matches from top to bottom in order, only the first match is run; 3. Multiple conditions can be listed by commas to match the same case; 4. There is no need to manually add break, but can be forced through; 5.default is used for unmatched cases, usually placed at the end.

First, use JavaScript to obtain the user system preferences and locally stored theme settings, and initialize the page theme; 1. The HTML structure contains a button to trigger topic switching; 2. CSS uses: root to define bright theme variables, .dark-mode class defines dark theme variables, and applies these variables through var(); 3. JavaScript detects prefers-color-scheme and reads localStorage to determine the initial theme; 4. Switch the dark-mode class on the html element when clicking the button, and saves the current state to localStorage; 5. All color changes are accompanied by 0.3 seconds transition animation to enhance the user

The settings.json file is located in the user-level or workspace-level path and is used to customize VSCode settings. 1. User-level path: Windows is C:\Users\\AppData\Roaming\Code\User\settings.json, macOS is /Users//Library/ApplicationSupport/Code/User/settings.json, Linux is /home//.config/Code/User/settings.json; 2. Workspace-level path: .vscode/settings in the project root directory

Installing the Emmet plug-in can achieve intelligent automatic closing of tags and support abbreviation syntax; 2. Enable "auto_match_enabled":true to allow Sublime to automatically complete simple tags; 3. Use Alt . (Win) or Ctrl Shift . (Mac) shortcut keys to manually close the current tag - it is recommended to use Emmet in daily life. The latter two methods can be combined, which is efficient and simple to set.

Use a dedicated and reasonably configured HTTP client to set timeout and connection pools to improve performance and resource utilization; 2. Implement a retry mechanism with exponential backoff and jitter, only retry for 5xx, network errors and 429 status codes, and comply with Retry-After headers; 3. Use caches for static data such as user information (such as sync.Map or Redis), set reasonable TTL to avoid repeated requests; 4. Use semaphore or rate.Limiter to limit concurrency and request rates to prevent current limit or blocking; 5. Encapsulate the API as an interface to facilitate testing, mocking, and adding logs, tracking and other middleware; 6. Monitor request duration, error rate, status code and retry times through structured logs and indicators, combined with Op

Use performance analysis tools to locate bottlenecks, use VisualVM or JProfiler in the development and testing stage, and give priority to Async-Profiler in the production environment; 2. Reduce object creation, reuse objects, use StringBuilder to replace string splicing, and select appropriate GC strategies; 3. Optimize collection usage, select and preset initial capacity according to the scene; 4. Optimize concurrency, use concurrent collections, reduce lock granularity, and set thread pool reasonably; 5. Tune JVM parameters, set reasonable heap size and low-latency garbage collector and enable GC logs; 6. Avoid reflection at the code level, replace wrapper classes with basic types, delay initialization, and use final and static; 7. Continuous performance testing and monitoring, combined with JMH

To correctly copy slices in Go, you must create a new underlying array instead of directly assigning values; 1. Use make and copy functions: dst:=make([]T,len(src));copy(dst,src); 2. Use append and nil slices: dst:=append([]T(nil),src...); both methods can realize element-level copying, avoid sharing the underlying array, and ensure that modifications do not affect each other. Direct assignment of dst=src will cause both to refer to the same array and are not real copying.