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Language APIs, Popular Concepts, Design Patterns, Advanced Techniques In the Browser

React: 50 shades of state

posted in JavaScript on 2020-07-21   react state management form components button viewmore compound state component theme onchange application state feature state data client text span const

We all know that one of the most challenging task in software development is state management. This is especially true for the JavaScript world. There are thousands of articles on this topic and so I decided to write another one 😁. I wanted to share my current thoughts on the different state types. I found that answering "What lives where?" question is far more important than the actual state management. Which more or less is an implementation detail.

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Recreating Facebook's Recoil library

posted in JavaScript on 2020-07-12   recoil facebook state management mycoil facebook s recoil counter atoms atom component library formattedcountervalue selector key function javascript subscribers hook const return

This weekend I decided to play with the new kid on the block - Facebook's Recoil library for managing state. I did the trivial counter example to see how it works. It's pretty simple idea so I wondered how much it takes to replicate its features. I found the exact answer - 70 lines of code. Obviously, my implementation didn't cover everything but it was fun so I decided to share my findings.

(A side note: I did not look at the code of Recoil. I didn't want to be bias on how to write my version.)

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Smart placeholders in your markdown

posted in JavaScript on 2020-05-06   markdown placeholders template annotation marked contentful https button part content stuff p p seemore const

I ❤️ markdown. I like its simplicity and minimalistic API which is good enough to cover most of needed HTML markup. At least for textual content. At work we have a small node based microservice that delivers data from Contentful in exactly markdown format. It's all working well but we started having cases where part of the text is in Contentful and the other part is in that microservice. For example when we have a button with a catchy design. We want to content manage the label of the button but the actual markup to be on our side.

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Pairify - how to match balanced string pairs

posted in JavaScript on 2020-03-11   pairify balanced matches javascript pairs decided type stack line starter token code const position function category https

I'm now actively working on a VSCode extension. I started it as a theme but then decided to add some more features. Like for example a tin line on the left side of the editor marking the current function scope. In order to do that I had to analyze the current file's code and find the lines that are included in that scope. The obvious approach will be to translate the code to AST and then traverse the tree finding the information that I need. This however will require the usage of a language server which now I don't want to deal with. So I decided to explore a brute force approach. Looping over the string characters and finding balanced matches. I quickly wrapped it into a library. I called it Pairify. It consumes text and returns an array of pairs. This blog post will show you how it works.

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AST fun. Remove a function call from your bundle

posted in JavaScript on 2020-01-13   javascript ast bundle object property path callee javascript esprima node const type

I'm working on a small library that has a logger. I'm bundling the app to a single file and I want to disable the logger for the production version. In this blog post we will see how I removed the logger.log calls from my bundle using AST (abstract syntax tree).

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Part 2: Riew - reactive view basics

posted in Riew on 2020-01-06   riew csp routine go javascript channels channels channel const javascript function ch view console log

Riew is a library based on communicating sequential processes (CSP). It is made to help with communication and synchronization between your view and business logic. It's distributed as a npm package, it has 0 dependencies and adds ~8KBs (gzip) to your application on production.

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Part 3: Riew - reactive view in patterns

posted in Riew on 2020-01-06   riew csp routine go javascript channels console log yield krasimir riew https github function state const

In this article we will see some use cases of Riew. Those are patterns which I found repeating while using the library. There are other blog posts part of the same series and I will suggest checking at least this one so you get a basic understanding before jumping into the code snippets below.

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Reactive view - the concept

posted in Riew on 2020-01-04   riew csp routine go javascript channels kitty ch const function view https react redux

Something bugs me last couple of years. I'm using React for some time now and there is always this doubt if I'm placing the business logic on the right place. I'm trying to be pragmatic, to follow best practices and listen what the community is saying. However, I still feel that something is not ok. This blog post presents the idea of the reactive view. That is nothing new per se but I came up with this term because it fits well in my idea.

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Make your objects iterable

posted in JavaScript on 2019-11-01   javascript iterator skills console log javascript const lastname object react parts user method

Just recently I became a fan of the iterable protocol. I knew about it for some time now but never actually integrated it on my own. I ended up using it to provide a nice API for one of my libraries and I thought that this approach worth sharing.

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Rethinking the Redux API

posted in JavaScript on 2019-09-10   redux const state login username password authenticated action function reducer

I really like Redux. I Love its ideas. The reducers for example - small pure functions that apply changes without side effects are nice way to model the mutations in the state. Redux also teaches us to use the one-direction data flow which makes our apps more predictable and stable. These two things fits well for what we are doing on the front-end - building user interfaces.

Of course there is nothing perfect and Redux as every other library has its own problems. In this article I want to explore some ideas for new APIs that will help solving the problems that I encounter. I’ll be happy to see your comments below.

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Jolly Roger - a 2KB micro-framework based on React hooks API

posted in JavaScript on 2019-04-20   time roger const state return function usestate yohoho action

The hooks API is a wonderful idea. There are some slick patterns involved that push the React development to a more functional approach. I'm interested in trying that new API and decided to use it for my latest project. However, after a couple of days, it looked like I can't build my app only with hooks. I needed something else. And that's mainly because each hook works on a local component level. I can't really transfer state or exchange reducers between the components. That's why I created Jolly Roger. It has similar helpers but works on a global app level.

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Build your own interactive JavaScript playground

posted in JavaScript on 2018-11-13   code function const console exports editor require file error js

Recently I spent some time working on my own JavaScript playground called Demoit. Something like CodeSandbox, JSBin or Codepen. I already blogged about why I did it but decided to write down some implementation details. Everything happens at runtime in the browser so it is pretty interesting project.

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React hooks: changing the mindset

posted in JavaScript on 2018-10-31   react function hooks count counter return useeffect state const usestate

If you use React you probably know about the so called hooks. They were officially announced at this year's ReactConf by Sophie Alpert and Dan Abramov. Their presentation could be seen here. I, same as many others got intrigued by this new feature. A little bit confused by if I like them or not but kind of excited. This article pretty much sums up my thinkings around React hooks and aims to give a balanced opinion.

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My take on Redux architecture

posted in JavaScript on 2018-04-06   state action redux const visible store function return counter type

Redux is a library that acts as a state container and helps managing your application data flow. It was introduced back in 2015 at ReactEurope conference (video) by Dan Abramov. It is similar to Flux architecture and has a lot in common with it. In this section we will create a small counter app using Redux alongside React.

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Meet the JavaScript pattern of the year or how to handle async like a boss

posted in JavaScript on 2017-11-24   generator player function result return position error const console log yield call player

Sometimes when you learn something new you get really excited. Excited to that level so you want to teach it to someone. That is the case with the concept which I found a couple of months ago. It is an implementation of the command pattern using generators. Or the well known saga used in the redux-saga library. In this article we will see how the idea makes our asynchronous code simpler and easy to read. We will also implement it ourself using generators.

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Getting from Redux to a state machine

posted in JavaScript on 2017-11-10   state error machine const user redux credentials login submit stent

This article is about Stent - a Redux-liked library that creates and manages state machines. Stent implements some of the Redux’s core ideas and in fact looks a lot like it. At the end of this post we will see that both libraries have a lot in common. Stent is just using state machines under the hood and eliminates some of the boilerplate that comes with Redux’s workflow.

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Post-transpilation or what is the real face of your code

posted in JavaScript on 2017-10-10   function user return firstname lastname var person object constructor greeting

If you write JavaScript today you probably use some sort of a transpilation tool. A tool that reads your hipster code and convert it to code that works in the browser. In this article we are going to see what is actually send to the browser and how exactly libraries like Babel polyfill some of the ES6 features.

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The powerful higher-order component pattern

posted in JavaScript on 2017-06-10   component function props react const job dependencies h1 return state

There are lots of things which I like in React. Mostly the fact that it teaches interesting patterns. One of my favorites ones is higher-order component. In this article we’ll do a couple of experiments and will see how powerful this approach could be.

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The Principles of Agile Development

posted in Architecture on 2012-07-10   agile development principles http net tutsplus sides http net fun developing software agile development agile articles general communication easy business people constructive

Agile or Agile Development – we hear these words more often these days. But do we really know what it is all about? How can it help us become more effective, while having lots of fun developing software? How can we use it to communicate with business people and make this communication easy and constructive for both sides?http://net.tutsplus.com/articles/general/the-principles-of-agile-development/

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AS3: runtime font loading (embedding)

posted in ActionScript on 2011-04-25   font field loader import flash swf public static const format font_export_name string font_file_name class

Flash is wonderful technology and has many advantages. Before a couple of years it was really popuplar to use it for displaying fonts that are not installed on the user's machine. Flash is still powerfull tool for such kind of tasks. These days I worked on a project which had to use a lot of fonts. It wasn't possible to embed all of them so I decided to implement runtime embedding.

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