Egghead Instructor Andrew Van Slaars

Andrew Van Slaars

Full stack developer, currently focused on building applications with JavaScript. I love learning new libraries, languages and tools and I'm passionate about sharing the things I learn with others.



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Browse Andrew Van Slaars's lessons.

showing 14 lessons...

Convert a QueryString to an Object using Function Composition in Ramda

Declaratively Map Data Transformations to Object Properties Using Ramda evolve

Select a Subset of Properties from a Collection of Objects in Ramda

Curry and Uncurry Functions with Ramda

Handle Branching Logic with Ramda's Conditional Functions

Create & Deploy a Universal React App using Zeit Next

Pick and Omit Properties from Objects Using Ramda

Declaratively Map Predicates to Object Properties Using Ramda where

Use Now alias for custom sub-domains

Use Secrets When Deploying Applications with Now

Change Object Properties with Ramda Lenses

Deploy a Node Application with the Now CLI

Add and Remove Items in Arrays using Filter, Reject and Partition in Ramda

Build a Functional Pipeline with Ramda.js

js tutorial about Convert a QueryString to an Object using Function Composition in Ramda

Convert a QueryString to an Object using Function Composition in Ramda

2:13 js

In this lesson we'll use a handful of Ramda's utility functions to take a queryString full of name/value pairs and covert it into a JavaScript object so we can access those properties in a more useful way. Along the way, we'll build up a composition and look at the tail, split, map and fromPairs functions, along with the crucial compose function.

js tutorial about Declaratively Map Data Transformations to Object Properties Using Ramda evolve

Declaratively Map Data Transformations to Object Properties Using Ramda evolve

2:44 js

We don't always control the data we need in our applications, and that means we often find ourselves massaging and transforming our data. In this lesson, we'll learn how to transform objects in a declarative way using ramda's evolve function.

js tutorial about Select a Subset of Properties from a Collection of Objects in Ramda

Select a Subset of Properties from a Collection of Objects in Ramda

2:59 js

In this lesson we'll take an array of objects and map it to a new array where each object is a subset of the original. We'll look at multiple ways to accomplish this, refactoring our code into a simple and easy to read function using Ramda's map, pick and project functions.

js tutorial about Curry and Uncurry Functions with Ramda

Curry and Uncurry Functions with Ramda

3:39 js

Most of the functions offered by the ramda library are curried by default. Functions you've created or that you've pulled in from another library may not be curried. Ramda's curry and curryN functions allow you to take a non-curried function and use it as a curried functions. In the case where you have a manually curried function and you want to just call it like a normal function, you can use uncurryN to get back a function that accepts all of the arguments at once.

js tutorial about Handle Branching  Logic with Ramda's Conditional Functions

Handle Branching Logic with Ramda's Conditional Functions

5:30 js

When you want to build your logic with small, composable functions you need a functional way to handle conditional logic. You could wrap ternary expressions and if/else statements in functions, handling all of the concerns around data mutation yourself, or you could leverage the conditional functions supplied by Ramda. In this lesson, we'll cover several of Ramda's conditional functions: ifElse, unless, when and cond

react tutorial about Create & Deploy a Universal React App using Zeit Next

Create & Deploy a Universal React App using Zeit Next

6:11 react

In this lesson, we'll use next to create a universal React application with no configuration. We'll create page components that will render on the server if accessed directly, but function as you would expect in the client. We'll use the routing capabilities included with next to create links between the components using pushState and we'll incorporate our own React component. Finally, we'll deploy the application to now with a simple command in the terminal.

js tutorial about Pick and Omit Properties from Objects Using Ramda

Pick and Omit Properties from Objects Using Ramda

5:39 js

Sometimes you just need a subset of an object. In this lesson, we'll cover how you can accomplish this using Ramda's pick and omit functions, as well as the pickAll and pickBy variants of pick.

js tutorial about Declaratively Map Predicates to Object Properties Using Ramda where

Declaratively Map Predicates to Object Properties Using Ramda where

2:34 js

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, cover the various facets of your conditions. In this lesson, we'll look at how this powerful function can be used for scenarios requiring a complex predicate function.

node tutorial about Use Now alias for custom sub-domains

Use Now alias for custom sub-domains

2:50 node

Now is a great way to deploy your node application, but the generated URLs aren't memorable or easily remembered. With Now's alias command, you can fix that. In this video lesson we'll cover how to add an alias to a deployment, giving you a custom *.now.sh subdomain, how to create an alias using your own custom domain name, how to list your aliases and finally how to remove an alias if you no longer want it.

node tutorial about Use Secrets When Deploying Applications with Now

Use Secrets When Deploying Applications with Now

4:17 node

Applications require a lot of sensitive information. Database passwords, API keys and secrets used for signing JWTs, just to name a few. If you're deploying your application using the Now CLI, you can deploy your secret information right through the CLI and give your code access to those secrets without exposing them directly in your source code. In this lesson, we'll cover how to add secrets to now, how to use a secret as the value of an environment variable and how to list and remove secrets in now.

js tutorial about Change Object Properties with Ramda Lenses

Change Object Properties with Ramda Lenses

4:46 js

In this lesson we'll learn the basics of using lenses in Ramda and see how they enable you to focus changes on specific properties of an object while keeping your data immutable.

node tutorial about Deploy a Node Application with the Now CLI

Deploy a Node Application with the Now CLI

4:02 node

Now offers a friction-free way to deploy node applications right from the terminal. In this lesson, we'll learn how to use the now CLI to deploy a node application, including the deployment of environment variables. We'll also look at how now retains each version of your application, how to see the running code right in the browser and how to remove a deployment when you no longer want that version.

js tutorial about Add and Remove Items in Arrays using Filter, Reject and Partition in Ramda

Add and Remove Items in Arrays using Filter, Reject and Partition in Ramda

2:09 js

We'll learn how to get a subset of an array by specifying items to include with filter, or items to exclude using reject. We'll also look at how to get the results from both filter and reject, neatly separated with partition.

js tutorial about Build a Functional Pipeline with Ramda.js

Build a Functional Pipeline with Ramda.js

5:37 js

We'll learn how to take advantage of Ramda's automatic function currying and data-last argument order to combine a series of pure functions into a left-to-right composition, or pipeline, with Ramda's pipe function.

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