I have a piece of javascript code that uses the ECMA6 dataset property to access an objects data-foo attribute of an element e. Unfortunately, this is not compatable with <=IE10. To combat this, I’ve rewritten my code to using a ternary operator, using dataset when supported and getAttribute when not…
Tag: ecmascript-6
How to set a variable on prototype in ES6 Classes?
We know that in the code above, methods someMethod and someMoreMethod would get attached to the prototype of someInstance object. But, what if we want to attach some property (not method) to the prototype. I tried doing the following but it throws error: Answer ES6 classes do not currently support fields. How…
Javascript ES6 TypeError: Class constructor Client cannot be invoked without ‘new’
I have a class written in Javascript ES6. When I try to execute nodemon command I always see this error TypeError: Class constructor Client cannot be invoked without ‘new’ The full error is mentioned below: What I am trying to do is, I have created a class and then created an instance of that clas…
require.cache equivalent in ES modules
ES Modules docs states: require.cache is not used by import. It has a separate cache. So where’s this separate cache? Is it accessible after all? I’m looking for invalidating module caching as it can be done in CommonJS modules (node.js require() cache – possible to invalidate?) Answer I saw…
Implement map using reduce
but just curious I also know that reduce is the base for map, foreEach and filter, I would want to try to implement above logic using reduce Answer Similar to other’s answers just more succinct:
Using Vue.set in object with multiple nested objects
I am trying to use Vue.set() to update a state object in Vue 2. This is what the object looks like: So far, I was updating it with this mutation. I’m mutating each entry separately because they have different content. Now, I’m trying to implement Vue.set() to avoid a change detection caveat. My pr…
How to understand JS realms
In ECMAScript specification there is notion of “realms” introduced: Before it is evaluated, all ECMAScript code must be associated with a realm. Conceptually, a realm consists of a set of intrinsic objects, an ECMAScript global environment, all of the ECMAScript code that is loaded within the scop…
Update the attribute value of an object using the map function in ES6
I am trying to code this in ES6. Below is what I am trying to achieve. Let’s say I have an array of objects called schools. Now, I want to write a function called editSchoolName which will take 3 parameters, schools (which is the array I have defined above), oldName and name. I will pass the name of the…
Vuejs Es6 class reactivity
i’m trying to have a computed property in vuejs associated to a es6 class. My Vue instance looks like this: My class looks like this If i try to do something like that: but the setter is never called, like the reactivity has been lost and i don’t understand why. I also try: I pass customClass as a…
Catch block not working in node fetch
Trying to learn, Javascript. Pardon if this is really a basic thin i am missing. I am trying to run node-fetch to a wrong url, and i expect that it should be catched and log my appropriate message. However when i run this file through node, it gives me uncatched error Answer Its this part that is uncatched: T…