Faced strange issue in JS. I receive error on this:  let a = [] let b = [1,2,3] b.forEach(a.push) TypeError: Array.prototype.push called on null or undefined     at Array.forEach (native)     at repl:1:3     at REPLServer.defaultEval (repl.js:262:27)...

This is the slideshow that we used:  http://www.littlewebthings.com/projects/blinds/  and this is the JS file:  http://www.littlewebthings.com/projects/blinds/js/jquery.blinds-0.9.js  However, this slideshow doesn't have a setting that makes it g...

I use Babel and Google Chrome Developer Tools with JavaScript source maps enabled. Given this code  function myFunc(elements) {   return elements     .map(element => element.value)     .filter(value => value >= 0); }   how can I pause execut...

g'day, I read meteor was going all ecmascript 6 - and thought awesome... "I never have to write 'function' again" - so quickly changed a bunch of functions over to lambdas... only to discover it doesn't work :(    If you write...

I'm creating a lambda function that executes a second function with a concrete params.This code works in Firefox but not in Chrome, its inspector shows a weird error, Uncaught TypeError: Illegal invocation. What's wrong of my code?  var make...

I thought QML supported lambda functions because of JavaScript's support of anonymous functions and the fact that functions are first class objects, but they don't work how I expected.  Take this code:  Item {     property var items: []...

I'm from a C# background but am new to React and JS in general. I was wondering if there was a way to use lambda functions when declaring an array, for example:  this.state = { arr: Array(9).fill( (i) => {<Foo index={i} />} ), };   I'...

I'm using a third-party library that has a function that takes functions as arguments. I'm doing some conditional checks to decide whether or not to add a particular function as a parameter and in some cases I don't want to provide a func...

I'm fairly experienced programming but quite new to TypeScript.  Trying to use it with jQuery and immediately ran into the 'this' issue with callbacks (such as $(document).ready.   Using $.proxy() is one way to go, but using TypeScript...

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