HN user

Luyt

3,269 karma

Software developer, Netherlands. motoom@xs4all.nl Python, C++, C, and others.

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Comments1,102
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microsculpture.net 10y ago

The Insect Portraits of Levon Biss

Luyt
15pts6
rachelbythebay.com 13y ago

Feedfetcher is still polling as if nothing happened

Luyt
2pts0
www.youtube.com 13y ago

Screen vs. tmux faceoff

Luyt
7pts0
www.theregister.co.uk 13y ago

32-way Raspberry Pi cluster

Luyt
2pts2
esr.ibiblio.org 13y ago

Building a better IRC client

Luyt
2pts0
esr.ibiblio.org 13y ago

National styles in hacking

Luyt
1pts0
esr.ibiblio.org 13y ago

Out on the tiles

Luyt
1pts0
esr.ibiblio.org 13y ago

Python speed optimization in the real world

Luyt
4pts0
www.cs.utexas.edu 13y ago

How do we tell truths that might hurt? (E. Dijkstra, 1975)

Luyt
66pts67
liquidr.com 13y ago

Liquid Robotics' marine robot completes 9,000 mile cross-Pacific journey

Luyt
1pts0
www.theregister.co.uk 13y ago

Adobe demands 7,000 years a day from humankind

Luyt
2pts0
www.theregister.co.uk 13y ago

VPN ban makes for nervy times behind Great Firewall

Luyt
4pts0
www.theregister.co.uk 13y ago

Patent suit targets Formlabs and Kickstarter

Luyt
3pts0
rachelbythebay.com 13y ago

Cogs, know when to fall off your wheels

Luyt
39pts7
rachelbythebay.com 13y ago

Password resets, airgapped devices, and data over video

Luyt
3pts0
www.codeproject.com 14y ago

Member Function Pointers and the Fastest Possible C++ Delegates, by Don Clugston

Luyt
2pts0
rachelbythebay.com 14y ago

When your "rank" is NaN

Luyt
3pts0
rachelbythebay.com 14y ago

Refuse to be mediocre

Luyt
3pts0
medriscoll.com 14y ago

The secret guild of Silicon Valley

Luyt
177pts48
mtomassoli.wordpress.com 14y ago

Currying in Python

Luyt
53pts21
rachelbythebay.com 14y ago

How many Apple accounts do you have to remember?

Luyt
31pts26
www.numbergrinder.com 14y ago

I’m an Engineer, Not a Compiler

Luyt
263pts151
rachelbythebay.com 14y ago

LaserJet display hacks for fun and more

Luyt
2pts0
stackoverflow.com 14y ago

Python metaclasses explained

Luyt
2pts0
esr.ibiblio.org 14y ago

Against decentralized bugtracking

Luyt
2pts0
tinyproj.tumblr.com 14y ago

Tinyproj: A recap of Day One

Luyt
26pts11
tools.ietf.org 14y ago

RFC2468: I remember Jon Postel, by Vint Cerf

Luyt
52pts4
www.readwriteweb.com 14y ago

The story of the Fail Whale

Luyt
2pts0
github.com 15y ago

Clojure and Compojure can run on Heroku's Cedar stack

Luyt
1pts0
vimeo.com 15y ago

Melvin the Magical Goldberg Machine

Luyt
1pts0

Tuples are immutable, but that doesn't mean they can't contain references to mutable objects.

When you want to use a tuple as a key in a dictionary, Python checks if all members of the tuple are immutable. If one or more of them aren't, you'll get an 'unhashable type' error.

A while ago, I was also sceptical about the walrus operator, although I use assignments in expressions all the time in C++. But when I was perusing a library written Python the other day, I found five spots in which the walrus operator would make sense - eliminating one line of source code without readability suffering from it.

He makes 30 microscopic pictures of a beetle, pastes them together, prints it on huge panels (for a museum exhibition). But you can also view them on the website, including at high zoom levels.

Chemtrails, really? I read this: "After sailing for three weeks with no signs of human activity, no power lines, no chemtrails, no evidence that we exist on the planet at all except for a mournful wooden cabin at Cape Adare, it’s jarring to see this open-air museum of prefabricated regret."

I'm sure the author means contrails ?

https://skeptoid.com/episodes/4027 "Chemtrails, real or not?"

Indeed. They mention the composition of the atmosphere, but the low pressure is conveniently forgotten about. The Mars atmosphere is like a vacuum: 0.00628 atm. Earth atmosphere normal pressure is 1 atm. Essentially, being on the surface of Mars is being in space. And what about the radiation? Mars has no magnetic field like Earth has. So the Solar Wind has free play on the surface.

I like the subdued colors in Towne's paintings. It reminds me of how I play videogames: with the saturation of the screen turned down to 50%, to make the colors less vibrant.

[dead] 10 years ago

The reason: "The first thing that makes running Just Landed difficult in the long-term is a serious lack of innovation in the flight data industry. An app like Just Landed relies on access to high quality flight data to function correctly. However, since the airline industry is extremely fragmented, and uses antiquated IT systems and many incompatible data formats, it is not practical for a small independent developer like us to negotiate data-sharing contracts with each individual airline, and then unscramble their jumbled data feeds into a usable format at a reasonable cost."

and a secondary one: the app ecosystem isn't worth it anymore:

"With well over 2 million apps by now (officially 1.5M as of July 2015), the iTunes App Store is an incredibly crowded place where it’s almost impossible to get noticed. Despite the persistent myth of the app developer millionaire, it’s extremely hard to make a profit — let alone a living — as an iOS app developer. The Google Play Store is a similar story, except with the added bonus of rampant piracy and a zillion devices to support. There really isn’t gold in them hills, at least not anymore, and independent app development will soon be in sharp decline, if it isn’t already.

Essentially, there’s a massive oversupply of apps, and the app markets are now saturated and suffering from neglect and short-term thinking by the companies who operate them. As competition has intensified, developers have resorted to giving their apps away, often at the urging of the app stores themselves. Consequently, the willingness of users to pay for apps, even unique apps like Just Landed, has declined sharply, while expectations of what an app should deliver have never been higher. Developers have been forced to get absurdly creative with their business models and marketing strategies just to make any income at all, rather than making the best product for their users. Just Landed, being a paid app with high running costs, has been on the wrong side of these trends, and what worked in 2012 no longer works in 2016."

The Rails Doctrine 11 years ago

The interview is from July 2009. I think Rails already had its ORM then. DHH says:

"The model part in an MVC application is where all the business logic is kept. Those are all the classes like ‘Post’ and ‘Category’ and ‘Author’ and all those things –say if you're making a weblog– you'd keep all that stuff in the Model. And you'd have all the logic about whether the author is allowed to make a post and how the relationship between posts and comments work together. Those are all sitting in the model, so that's all the business logic, very often backed by a database in some sense, not always, but most of the time. And that's where in Rails we're using something called ‘ActiveRecord’. Which is this way of mapping database tables to objects, and then decorating those objects with logic."

The Rails Doctrine 11 years ago

I transcribed an interview with DHH [0] in which he also explains his motivations for choosing Ruby (instead of PHP or Java, for example), and where he explains some design principles for Rails.

[0] http://www.transcribed-interview.com/dhh-rails-david-heineme...

"One example I always pull out is “what you gonna call the primary key in your tables?” When I was working with PHP and Java, every single shop, almost every single application, would have its own naming scheme. Some would say they have the ‘Products’ table and then they'd have ‘productid’, others would have ‘product_id’, some people would have ‘prod_id’ or ‘p_id’ or ‘P_id’, and every time somebody made a new design decision it meant configuration. You now have to tell your models, your objects, how they're going to talk to this database table. Because it needs to know what the hell you called the freaking primary key column, and it just doesn't matter! Who cares what the primary key column is called? It just doesn't matter. It's going to have zero impact on the usefulness of your application."

and

"‘Dont repeat yourself’ is all about not having the same intentions spread out in multiple places. Don't have one configuration. If you're calling something, let's again take the example of the primary key. If you're calling that for ‘id’ you shouldn't have to configure that in three different places that all have to work together and all have to be changed together. You should just pick one authoritative place to have that information stored. And then you can make changes from there. It also goes with the the whole Ruby idiom: we don't want those Java boilerplate ten line things: that's repeating yourself. If you have the same idiom, if you have the same intentions, that should really be exceedingly a short expression. And that goes up throughout the entire framework. Just keep one place to change those things, and keep the idioms very short."