In this lesson, we’ll use a Maybe to safely operate on properties of an object that could be undefined. We’ll use our initial code as the basis for a prop utility function that can be reused with different objects and various property names. Instead…
In this lesson, we’ll look at the propPath utility function. We’ll ask for a property multiple levels deep in an object and get back a Maybe. We’ll get a Just when the property exists at our path and a Nothing if any part of the path is undefined. co…
Javascript has three different kinds of properties: named data property, named accessor property and internal property. There are two kinds of access for named properties: get and put, corresponding to retrieval and assignment, respectively. Please r…
A Javascript Proxy object is a very interesting es6 feature, that allows you to determine behaviors whenever a property is accessed in a target object. In this lesson, you will learn how to use it to prevent users from accessing specific properties i…
Sometimes you need to filter an array of objects or perform other conditional logic based on a combination of factors. Ramda's where function gives you a concise way to declaratively map individual predicates to object properties, that when combined,…
All object members are public in JavaScript. var myobj = { myprop : 1, getProp : function() { return this.myprop; } }; console.log(myobj.myprop); // `myprop` is publicly accessible console.log(myobj.getProp()); // getProp() is public too The same is…
Principle Make variables shouldn't be changed stand out using all caps. Add constants as static properties to the constructor function. // constructor var Widget = function () { // implementation... }; // constants Widget.MAX_HEIGHT = 320; Widget.MAX…
