Arrow Functions
js-arrow-functions
Question Banks
JavaScript `this` and Arrow Function Code Traces
Six traces covering lost-`this` on extracted methods, arrow inherits-from-enclosing, function-as-constructor return, IIFE `this`, and static vs prototype methods.
JavaScript Function Fundamentals Quiz
Four day-one essentials about functions: how to define them, when to choose declaration vs expression vs arrow, default parameters, and rest/spread.
JavaScript Lost-this and Four Fixes Quiz
Repair a method whose inner regular function loses `this`, four ways (arrow function, `bind`, save-this-in-self pattern, explicit `.call`), plus an explainer on lexical-vs-dynamic this binding.
Community
The this Keyword: Six Rules and the Edge Cases
The six rules that fully decide the value of this in JavaScript: lexical for arrows, new, explicit binding, implicit binding, and the strict/sloppy default. Plus the four-step diagnostic I use on every this bug.
Mastering Closures in JavaScript
What a closure actually captures (variable bindings, not values), why the loop-with-var bug exists, and the real-world patterns that lean on closures: module pattern, currying, and React useCallback.