JavaScript: The bad parts

Key Points:

• Floating Point Arithmetic: JavaScript follows the IEEE Standard for Floating-Point Arithmetic, leading to unexpected results like 0.2 + 0.1 equaling 0.30000000000000004. This isn't a flaw in JavaScript but a characteristic of how numbers are represented in most programming languages and computers.

• Type Coercion: Being a dynamically and weakly typed language, JavaScript can sometimes perform implicit conversions between different types, which can be confusing. For example, using == can lead to unexpected type coercions, thus the recommendation to use === for strict equality.

• Automatic Semicolon Insertion (ASI): JavaScript can automatically insert semicolons, but this feature isn't always reliable. It’s better to explicitly insert semicolons to avoid potential issues.

• Bottom Values (null, undefined, NaN): JavaScript has multiple 'bottom' values representing non-existent or undefined values, which can be confusing and is seen as a design flaw.

• Increment and Decrement Operators: The use of ++ and -- is seen as unnecessary and can reduce code readability. It’s recommended to use + 1 or – 1” instead for clarity.

References

1. https://www.smashingmagazine.com/2023/12/making-sense-of-senseless-javascript-features/