What’s Wrong with This JavaScript Loop? Exploring Common Coding Pitfalls

The piece, originally reposted from the "菜鸟教程" public account, presents a series of JavaScript code screenshots intended for learning basic constructs such as if statements and for loops. It notes that a loop running only 40 times is safe, but scaling to 400 iterations could cause a crash.

One example demonstrates a hard‑coded password variable, discussing how the naming (e.g., passWord) may be intentionally confusing and how engineers can locate such passwords via browser debugging tools, raising potential security concerns.

The article then displays several code‑style examples, highlighting inconsistent indentation, excessive nesting of else blocks, and mismatched braces (e.g., counting how many }) appear). It points out that while while loops are sometimes insufficient, the presented snippets satisfy the visual output shown in the accompanying images.

Another segment features a quirky odd‑even detection routine, followed by an improved version that streamlines the logic.

Finally, a minimalist UI example is shown, created under a tight budget of 3000 CNY, demonstrating how a simple display can reassure users despite limited resources.

The article concludes with a playful call for readers to share other “annoying code” they have encountered.