Why is it, in general, a good idea to leave the global scope of a website as-is and never touch it?
Câu trả lời
Leaving the global scope of a website as-is and not introducing new variables or functions into it is generally considered a good practice for several reasons:
Namespace Pollution: Adding too many variables or functions to the global scope can lead to namespace pollution. This is where different parts of a codebase inadvertently use the same global variable or function names, which can lead to unexpected behavior and bugs that are difficult to track down[4][5].
Maintainability: Code that relies heavily on the global scope can become difficult to maintain over time. It's harder to understand the dependencies between different parts of the application when global variables are involved, as it's not always clear where a variable was defined or modified[5].
Modularity: Keeping the global scope clean encourages modularity. By using local scopes, developers can create self-contained modules that are easier to reuse, test, and manage. Modules can expose a limited interface to the rest of the application, which reduces the risk of conflicts and makes the codebase more robust[5][6].
Collision and Overwriting: In a shared environment like the web, where multiple scripts and libraries may be loaded, there's a risk of global variables and functions being overwritten by others. This can cause parts of a website to fail silently or behave erratically[4].
Security: Global variables can be accessed and potentially tampered with by any script included in the page. This can pose a security risk, especially if the global variables contain sensitive information or are used to control critical functionality of the website[4].
Performance: Excessive use of the global scope can lead to performance issues. Global variables live as long as the application is running, which can lead to increased memory usage. Also, looking up global variables can be slower than local variables due to the way scope resolution works in JavaScript[13].
