WTFJS is a curated collection of JavaScript “gotchas” and puzzling examples that reveal surprising corners of the language. Each entry presents a small snippet, explains why the behavior occurs, and ties it back to the specification or engine rules. The repository covers coercion quirks, edge-case comparisons, floating-point oddities, prototype traps, and scoping pitfalls, among others. It’s designed as both a fun read and a serious learning aid, helping developers build an intuition for how JavaScript evaluates expressions. By highlighting common misconceptions, it encourages safer coding patterns and more reliable mental models. Teachers, interviewers, and learners use it to spark discussion and deepen understanding of JavaScript’s semantics.
Features
- A collection of unexpected or counter-intuitive JavaScript examples
- Detailed explanations of why such surprising behaviors occur
- Educational resource designed to deepen understanding of JS specification nuances
- Presented in a lighthearted, engaging style—“just for fun” motivation
- Highlights fundamental JS pitfalls like coercion oddities, type quirks, edge-case comparisons
- Freely accessible open source repository with contributions encouraged