JavaScript Allongé is a book about programming with functions that uses the JavaScript programming language for the examples and exercises. JavaScript Allongé is for: — Programmers learning JavaScript who want a thorough grounding in its fundamentals rather than a cursory treatment of its syntax. — Programmers already using JavaScript who want to go back and take a deep dive into programming with functions and combinators. — Any programmer curious about programming with functions. JavaScript Allongé's primary focus is functions as first-class values and topics built on those fundamentals such as objects, prototypes, "classes," combinators, method decorators, and fluent APIs.