JavaScript Quotes

“Event-driven JavaScript programs register callback functions for specified types of events in specified contexts, and the web browser invokes those functions whenever the specified events occur. These callback functions are called event handlers or event listeners,”
― David Flanagan, JavaScript: The Definitive Guide: Master the World's Most-Used Programming Language

“That callback function is invoked asynchronously when getJSON() returns,”
― David Flanagan, JavaScript: The Definitive Guide: Master the World's Most-Used Programming Language

“When a Promise-based asynchronous computation completes normally, it passes its result to the function that is the first argument to then().”
― David Flanagan, JavaScript: The Definitive Guide: Master the World's Most-Used Programming Language

“At a simple syntactical level, the then() method is the distinctive feature of Promises, and it is idiomatic to append .then() directly to the function invocation that returns the Promise, without the intermediate step of assigning the Promise object to a variable.”
― David Flanagan, JavaScript: The Definitive Guide: Master the World's Most-Used Programming Language

“Instead of passing our callback function directly to getJSON(), we instead pass it to the then() method. When the HTTP response arrives, the body of that response is parsed as JSON, and the resulting parsed value is passed to the function that we passed to then().”
― David Flanagan, JavaScript: The Definitive Guide: Master the World's Most-Used Programming Language

“The keywords async and await were introduced in ES2017 and provide new syntax that simplifies asynchronous programming by allowing you to structure your Promise-based code as if it was synchronous.”
― David Flanagan, JavaScript: The Definitive Guide: Master the World's Most-Used Programming Language

“Promises, new in ES6, are objects that represent the not-yet-available result of an asynchronous operation.”
― David Flanagan, JavaScript: The Definitive Guide: Master the World's Most-Used Programming Language

“Most real-world computer programs, however, are significantly asynchronous. This means that they often have to stop computing while waiting for data to arrive or for some event to occur.”
― David Flanagan, JavaScript: The Definitive Guide: Master the World's Most-Used Programming Language

“Another problem with callbacks is that they can make handling errors difficult. If an asynchronous function (or an asynchronously invoked callback) throws an exception, there is no way for that exception to propagate back to the initiator of the asynchronous operation.”
― David Flanagan, JavaScript: The Definitive Guide: Master the World's Most-Used Programming Language

“JavaScript is not a functional programming language like Lisp or Haskell, but the fact that JavaScript can manipulate functions as objects means that we can use functional programming techniques in JavaScript.”
― David Flanagan, JavaScript: The Definitive Guide: Activate Your Web Pages

“JavaScript derives its syntax from Java, its first-class functions from Scheme, and its prototype-based inheritance from Self. But”
― David Flanagan, JavaScript: The Definitive Guide: Activate Your Web Pages