Lodash & Folktale Partial Function Differences

Introduction

At work I was trying to practice doing more composing of functions, and to do so you create a lot of partial functions, often through currying. Sometimes, the functions aren’t built for partial/currying, or the parameters are in an awkward order. Lodash offers partialRight instead.

However, I was trying to use all of Folktale’s functions instead of my normal use of Lodash in an effort to force myself to learn the differences. They both offer many of the same features like curry, partial, compose etc. but with different function signatures. I came to like the Folktale’s v2 version of partial called partialize and wanted to briefly talk about why.

Below, I’ll go over parsing a time & weather web service JSON response. We’ll show parsing the data using both Lodash and Folktale functional partials. This should teach you the difference between the 2 libraries approaches to function partials.

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Node.js Crash Course

Introduction

I’ve been doing Node full-time at work and noticed a lot of other people lacking a centralized resource to get up and running quickly. There are a lot of wonderful resources out there for Node, a Google search away, but hopefully this document should get you coding quickly as well as able to communicate effectively with other Node developers.

I’ve tried to write this list in order of most important things you need to know. Feel free to skip around.
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Easier Error Handling Using Async/Await

Introduction

At work, someone asked if there were any better ways to handle errors when using the async/await syntax in JavaScript. They didn’t like their beautiful, short, and readable lines of code suddenly wrapped with try/catches. I’ve also been frustrated with a variety of the enthusiasm online the past couple years around async/await only to be shown code examples that completely ignore error handling.

Below is an easier way to handle errors using async/await by returning what’s known in Functional Programming as an Either. Mine isn’t as formal as the FP community’s “left right”. It’s just simple JavaScript Object that follows the Node callback naming convention somewhat.

tl;dr; First option is to create Promises that only call success with an Either, and Promise.resolve in the catch with an Either, or second option is to use a simple wrapper function.
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Asynchronous Programming

Introduction

JavaScript is an asynchronous programming language in Node and in the browser. In many languages such as Java, C#, Python, etc. they block the thread for I/O. What this means is when you make an HTTP/ajax call or read a text file for example, the runtime will pause on that line of code until it is successful or failure.

JavaScript does the opposite. Using callbacks or Promises, you basically leave a phone number to call when those operations are done, while the rest of the synchronous code keeps going. In this article we’ll talk about why, give examples from JavaScript and compare against a blocking language, and show you some tips to help.

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