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Derk-Jan Karrenbeld profile picture

Derk-Jan Karrenbeld

Still a random idiot

Location Rotterdam, The Netherlands Joined Joined on  Personal website https://derk-jan.com github website twitter website

Education

Some comp. sci. @ Delft, University of Technology

Work

Partner & Operations Manager at XP Bytes

All 97 comments

Javascript call by value or by reference, actually by sharing

^ this :)

JavaScript, Ruby and C are not call by reference

Call by sharing is explicitly mentioned at the bottom of this...

Status instead of isLoading boolean?

The _callable Global Objects are a gem ✨. I also recommend ...

Status instead of isLoading boolean?

!!value is effectively the same as Boolean(value) and will th...

Status instead of isLoading boolean?

You did miss something. The && will cast the left-h...

Common UseEffects mistakes that even seniors are making

The post is full with bad advice. It's a good attempt, but a ...

Advent of Code 2020 Solution Megathread - Day 16: Ticket Translation

Today was a LOT of fun! I finished it quickly, but only was a...

Advent of Code 2020 Solution Megathread - Day 15: Rambunctious Recitation

Didn't really find this one interesting. Apparently it's a kn...

Advent of Code 2020 Solution Megathread - Day 13: Shuttle Search

I don't know about those theorems. It's a prime factorisation...

Advent of Code 2020 Solution Megathread - Day 12: Rain Risk

There are (at least) two ways to "model" the solution: polar ...

Advent of Code 2020 Solution Megathread - Day 10: Adapter Array

Yeah. Once you do a series of solutions using Dynamic Program...

Advent of Code 2020 Solution Megathread - Day 11: Seating System

OOP in Ruby; I enjoyed writing this! require 'benchmark' ...

Advent of Code 2020 Solution Megathread - Day 10: Adapter Array

Certainly. It's dynamic programming! In this case, the prob...

Advent of Code 2020 Solution Megathread - Day 9: Encoding Error

Because of the contiguous set limitation, it always works. Yo...

Advent of Code 2020 Solution Megathread - Day 10: Adapter Array

I didn't really have fun today. My final solution in Ruby too...

Advent of Code 2020 Solution Megathread - Day 9: Encoding Error

This is the first day I did not OOP it up, because I felt laz...

Advent of Code 2020 Solution Megathread - Day 8: Handheld Halting

Another OOP solution in Ruby. require 'benchmark' class I...

Advent of Code 2020 Solution Megathread - Day 7: Handy Haversacks

Part 1 is a reachability problem, Part 2 is a Depth first sea...

Advent of Code 2020 Solution Megathread - Day 6: Custom Customs

Only took a few minutes today; here is what I got in Ruby: ...

Advent of Code 2020 Solution Megathread - Day 5: Binary Boarding

Today I have two implementations in Ruby for ya. require '...

JavaScript loop querySelectorAll results

I recommend it! Don't bin IE because you (and I) hate it, b...

Advent of Code 2020 Solution Megathread - Day 4: Passport Processing

I feel this reads as quite elegant in Ruby -- or at least my ...

JavaScript loop querySelectorAll results

I use death-to-ie11.com/ often; and charge customers/clients ...

JavaScript loop querySelectorAll results

Good list of the options! Instead of [].forEach, I believe t...

Advent of Code 2020 Solution Megathread - Day 2: Password Philosophy

What I came up with in Ruby: require 'benchmark' class Pa...

Advent of Code 2020 Solution Megathread - Day 3: Toboggan Trajectory

Here is my Day 3 in Ruby require 'benchmark' class TreeGr...

Advent of code - Day 2

It doesn't need to be pretty! As long as it does the job righ...

Const Is A Lie In JavaScript & Mastering UnitΒ Testing

This article: const doesn't mean constant value; if you th...

Good Bye Web APIs

It would be helpful if experienced people stopped making stat...

"Variables declared with const cannot change" ... well kinda...

Hi there Austin, I saw on Twitter that you may think that th...

Good Bye Web APIs

Let's be real. In practice, how many apps have multiple API ...

Good Bye Web APIs

The server only exposes the type of the attributes and the s...

localStorage vs cookies: the "tabs vs spaces" sterile debate of web development πŸ™„

It might have been the implicit intention, but I do think the...

localStorage vs cookies: the "tabs vs spaces" sterile debate of web development πŸ™„

Saying "don't use localStorage because its accessible by Java...

The State of Open Source: Currents 2020 Survey

Unfortunately there was no feedback question in the survey, o...

Understanding JavaScript Prototype

It's hard to not judge articles when they have so much misinf...

Type | Treat Challenge 1

This was fun! Thanks :) Der...

Expo SDK 38 is now available

Upgrade your node. The error is pretty clear. You're on node ...

Expo SDK 38 is now available

Check the Feature Requests to see if yours is listed, or crea...

Expo SDK 38 is now available

No. You can use 16.11.

Expo SDK 38 is now available

No, it won't be supported, because uneven node versions never...

Expo SDK 38 is now available

Check out these lines in the expo-cli repo: ...

Expo SDK 38 is now available

If I could get the expo/expo repo running on my (windows) mac...

Expo SDK 38 is now available

Yep, expo upgrade finally worked smoothly (I had issues with ...

Expo SDK 38 is now available

Missing in this post (for me): It's now built against React...

Expo SDK 38 is now available

On Android, there are three ways the bottom bar can show up: ...

Expo SDK 38 is now available

New Status Bar module Wooo. But not possible to update th...

Forward arguments in shell

Absolutely! But when I needed to do this, I did not have that...

JavaScript, Ruby and C are not call by reference

No need to apologise for asking! I've changed the example...

Hacktoberfest Completion Thread

I forgot I signed up, despite me inviting the DEV community...

A little hacktoberfest riddle

At least it's not the most obvious transformation :) (but r...

Welcome To Your Silicon Valley Life: Starting Your First Tech Job

Ugh. So many of this resonates exactly with what my life wa...

Hacktoberfest Starts in Six Days πŸŽƒπŸŽ‰

We have quite a bit of OSS opportunity at Exercism! ...

Unhealthy Code: Primitive Overuse

Ah. That makes sense to me! I'm personally not a fan of th...

Unhealthy Code: Primitive Overuse

The canonical term you'll find in other documents including...

What is the oddest JavaScript behavior?

Absolutely true. I was only referring to the use of the wor...

What is the oddest JavaScript behavior?

It's not insane. null, like nil in ruby, a singleton instan...

What is the oddest JavaScript behavior?

It does not

The 7 Most Popular DEV Posts from the Past Week

It has far less views and reactions. I think that's how the...

Tetris: Building a game using JavaScript

Tetris: Choosing the ...

Tetris: Building a game using JavaScript

The next post is coming! It's taking a bit longer to write....

Javascript String Methods You Must Know to Become an Algorithms Wizard

Yes, that is what I was saying as well :) The ref links al...

Javascript String Methods You Must Know to Become an Algorithms Wizard

JavaScript has, as you might be aware, a specification call...

Write a poem about code

As listed on xpbytes.com/404, written in 2015 Bit...

Tetris: Building a game using JavaScript

~Seven years ago, together with another student (who I stil...

Tetris: Building a game using JavaScript

I'm panning on making this a weekly, probably "Friday" thin...

JavaScript, Ruby and C are not call by reference

Yes, concurrency/parallelism is still on my list to write a...

JavaScript, Ruby and C are not call by reference

i.e. we care about the object, not the references. This is...

JavaScript, Ruby and C are not call by reference

Valentin made a good comment and jmc went into more detail....

JavaScript, Ruby and C are not call by reference

To be fair, it made more sense in the 60s. This is absol...

JavaScript, Ruby and C are not call by reference

It happens! We're all only human :) Being on the spectrum,...

JavaScript, Ruby and C are not call by reference

Happy to write it! I did try to look up a bit of the lite...

JavaScript, Ruby and C are not call by reference

If you look at the original article you can see a discussio...

JavaScript, Ruby and C are not call by reference

Thank you! Looking for my next subject, so let me know if t...

JavaScript, Ruby and C are not call by reference

In JS among others, the value is actually always a referenc...

JavaScript, Ruby and C are not call by reference

The post that sparked this article: ...

Passed By Reference Vs. Value In Javascript

JavaScript, Ruby and ...

The Weird History of JavaScript

Also: thank you so much for taking the time and writing it li...

The Weird History of JavaScript

Given your response, yes I would never use either of those th...

Passed By Reference Vs. Value In Javascript

Don't worry! Keep recapping. Like I said, it holds value :)...

Passed By Reference Vs. Value In Javascript

I will!

What does your Junior interview process involve?

We recently hired new juniors and this was the process: I...

The Weird History of JavaScript

EDIT: I'm sorry if I've come across as overly assertive in...

Passed By Reference Vs. Value In Javascript

I guess I'll write an article. That said, I completely und...

Weird things you can (but shouldn't) do with JavaScript tagged templates

For completeness πŸ”₯ ...

Passed By Reference Vs. Value In Javascript

If you try to look this up, most resources will actually me...

Passed By Reference Vs. Value In Javascript

Whilst this is a great post and the overal information is cor...

The Weird History of JavaScript

Github is also, unfortunately, not a perfect reflection. Th...

The Weird History of JavaScript

"Most used" via "StackOverflow" is not (necessarily) most use...

Writing a dev.to blog post with VSCode

422 would probably be more appropriate, but yes, a 4xx stat...

Writing a code analyzer in TypeScript (from scratch)

C# has a different approach for two-fer and Ruby is going t...

Writing a code analyzer in TypeScript (from scratch)

Great questions! I am actually writing the analyser code t...

PWAs are our future

Those features we're not present in Chrome when PWAs landed...

Using arrow functions might be costing you performance

That is the point ;) This article is pretty fear mongering a...

Using arrow functions might be costing you performance

This might be more interesting to compare: jsperf.com/fufuf...

PWAs are our future

Apple is actually behind on multiple fronts but finally cat...

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