A collection of tricky JS interview questions
Implement a polyfill for Promises in the browser which works for ie8
Okay, so not knowing this question is totally fine. It does not make you a bad developer. More over most of the times if you are asking to implement something like this, you'd probably copy something from Stack overflow or some blog site on Google. I realise people may get intimidated by core JS questions during interviews, and not knowing some of it at that moment isn't a testament to how you are . Nevertheless a company's bench mark are such questions.
The questions have an editor button, which will open a VS code editor, and let you try out a few questions.
Implement the Array.map method on the Array Prototype
Implement the Array.filter method on the Array Prototype
Implement the Array.reduce method on the Array Prototype
Implement the Array.forEach method on the Array Prototype
Implement the Function.bind method on the Function Prototype
Implement Async.parallel, which executes a set of asycn tasks parallelly
Implement Async.series, which executes a set of asycn tasks in series
Write a function which will memoize subsequent calls to a function
Write a method which will implement Promise.all
Write a method which will flatten any array into a 1D array
Attach a listener to an array which gets triggered when an item is pushed into the array
Implement a class / function / utility which exhibits an event dispatcher mechanism