Programming

“I like small languages,” said a friend of mine.

“Yeah, me too. Wait. What do you mean by small languages?” I replied

“You know, small. JavaScript. Lisp. Small, stuff… Not big,” he faltered as he struggled with the rest of his sentence.

That led to a series of discussions about what a small language is. We eventually enumerated a list of languages which we knew and could classify. Languages which we mutually agree are small are listed in small fonts; languages which we mutually agree are large are listed in large fonts:

• C
• Scheme
• Lua
• Python
• Go
• JavaScript
• Haskell
• Java
• C#

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I recently visited China (my writeup was in three parts: Part I, Part II, Part III). An incident of particular note was in a taxi in Nanjing. Picture this: The driver is on the left side of the vehicle. On left edge of the windshield, a Samsung Galaxy Note sits on windscreen mount, connected to the cigar lighter on his right. The cigarette lighter also powers another smaller feature phone which sits on top of his dashboard. Next to the air conditioner vent of the front panel, a walkie talkie sits on its cradle.

We were on a fairly long journey (about 20km ish), and the driver was talking to us, trying to upsell us his services for the whole day. We talked about the local sights, the museums and what nots. Then CRRSSSHHH, an incoming message from the walkie talkie – it was something traffic related. The driver pressed the transmit button on the walkie-talkie, acknowledging the message. Then came a different TCHSSHH sound. A woman’s voice came into hearing. She asked about lunch. The driver leaned forwards, picked up the feature phone, and pressed a button and talked into it, explaining that he was with passengers and his general direction. Upon finishing that conversation, he continued our conversation, picking up from where he left off.

This continued to happen throughout the journey – the driver would be switching between different modes of verbal communications – real life, push to talk, walkie talkie and even his mobile phone. The driver was dealing with 4 different networks at the same time (walkie talkie – some kind of trunked system, since most of it were traffic related; the push-to-talk feature phone – which I assume to be some kind of PTT powered by cellular tech; mobile phone – full duplex radio; and talking with the passengers of the car). That sparked an idea.

Here’s a bit more background. I had developed an interest in trunked radio networks and half-duplex communications when my way-more-accomplished-than-me partner was working as an E&E engineer for the telecomms industry* I think she’s more accomplished than I am, given that she’s now working for a certain search engine company while I have tried and failed at least 5 times with that same company, twice within the last 7 months . So I had some good ideas on how CB and trunk radio networks worked.

At the same time I was having a bit of trouble with the VPN the previous night. The solution was simple – I ended up rolling my own VPN on AWS, swapping elastic IPs for the EC2 instance every few hours and updating encryption key everyday. In short, it was a mess.

So the idea was born: what if you could have an ad-hoc (read: P2P) chat network that was private (read: encrypted), and you could juggle different networks at the same time? After a few rounds of refinement of the idea, I started working on the prototype application that night.

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The week before last was a terrible week for me. It was one week after I had published my books. I was looking to take some time off from updating the books. After about 6 months being self-employed, doing the things I love to do, I felt it was time for me to return to the workforce. Let’s face it, it’s not easy to be self employed and get a steady paycheck. So I started looking for jobs.

All was well. I had applied to a number of jobs that I was interested in. By the end of the week however, I had nothing – nobody called back. Naturally, coming off the high of having just published a couple of books, it was crushing.

Remember a few months ago, I was mulling over acquiring a tablet? Out of sheer coincidence, I came into posession of a Nexus 10 a few days after I blogged that entry. It’s an older model, but hey, beggars can’t be choosers. Despite coming to possession of the tablet, I never really used it.

Anyway, back to the week before last. Combined with the fact that I got rejected for those jobs that I wanted plus a few more not so nice news, I was feeling pretty shitty about myself. So on Friday evening, I altered my state of mind chemically to relax a little.

After some drinks, I took out my tablet and fiddled with it while relaxing with pineapples. I decided to download my favourite game on tablets since 2011 – Jetpack Joyride. Now, when your brain is under the influence, time seems to slow down – your body appears to lag. Specifically my eyeballs felt like they were lagging. I kept looking at the right of the screen, and I could feel my eyes darting to look at the right and back to Barry on a very regular basis.

This led me to ask a question: what does Jetpack Joyride look like when one’s eyes are tracked? What would a heatmap look like? Clearly there are eye tracking devices out there like the EyeTribe or Tobii which is fantastic. But I didn’t have access to any of those. The front-facing camera of my tablet appeared to frown at me. Then it hit me: why not use it to do eye tracking?

So I dragged myself to the computer, and started learning how to write Android apps. To their credit, the Android developer page is absolutely easy to use – if an intoxicated person can read and create an app in about an hour, you know it’s bloody good documentation. I didn’t get far, except to capture videos and detect my face, which is easy stuff anyone can do. I went to bed.

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Last year I wrote a blog post comparing programming languages to driving experiences. Today in the chatroom, my friends and I were talking about config management tools. I’ve had the opportunity to use most of them, so I compared them to operating systems as such: CM Tool OS Feels Like Ansible Mac OS Here's the one way to do things, chosen Your Lord and God, Steve Jobs. You can do things other ways too, but be prepared for a little pain Salt Linux Do whatever the fuck you want to do. [Read More]

After a long time spent in the editing room, I finally published both books that I kept talking about for the past few weeks in my blog. You can get them here: Introduction to The Books Underhanded JavaScript catalogues the various kinds of “naughty” things that can be done with JavaScript. These are followed by explanations as to why they happen, and also how to maliciously use them (in tongue-in-cheek tones of course, I don’t expect you to actually deploy such code. [Read More]

Oh wow, I’ve just had my first “satori” experience of rubber ducky debugging in a very very long time. I first tweeted that I ran into a bug in Go, where upon running my code (with go run): Oh wow, ran into my first indeterminate bug in Go. Same code compiled twice produces two different results. Amazing — Chewxy (@chewxy) February 26, 2014 I had a problem where when I ran the same code multiple times, there would be occasions where the program panics. [Read More]

After I gave my talk on JavaScript (really, I was there trying to shamelessly plug my book - Underhanded JavaScript and its alternate title: JavasScript Technical Interview Questions), there was a Q&A session. I could answer most questions, but Khalid Hilaby asked me a very interesting and quite general question on JavaScript number types. He had simply wanted to know more about floats in JavaScript and why they act so strangely. While I could answer the question, I felt I didn’t answer it well enough. I loaded my article on Pointer Tagging in Go to explain the structure of a floating point number, explained a bit on floating point arithmetic, and how in the past they had to have special CPUs for floating points (FPUs)* Nowadays they're all integrated , and then sort of meandered from there.

Now that I am back in Sydney and well rested, I thought I’d give the question a second try. The result is the article - What Every JavaScript Developer Should Know About Floating Points on Flippin’ Awesome. This is the full unedited version before I edited down for length and appropriateness for Flippin’ Awesome.

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I gave a talk on Javascript recently at Javascript.my‘s unshift() miniconf in Kuala Lumpur. After regretting giving many talks without a recording to track my performance improvements when giving talks, I decided that starting this year, I would record and transcribe my talks. Here’s the first one for 2014. The slides are embedded here as well.

I had originally planned to record my talk and use an automatic transcriber to transcribe. But the recording quality was indeed quite poor as my phone battery was running out. I had to use Audacity to clean it up quite a bit. And despite that, automatic transcription with OS X’s Dictation didn’t work as well as I expected it to.

Anyhow, here’s the transcription of my talk. A lot of bits were filled in and edited (I really have a lot of uh, and ums when I speak) as the recording got quite garbled as time went on. Towards the end it was a totally unrecognizable warble. I was scheduled to give a 30 minute talk but I ended up talking for about 50 minutes. The last 20 minutes are not transcribed.

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So… Hacker News went down for about a day. I lost my main source of procrastination (reddit contained all purple links). So what did I do? I got productive. I wrote about 20% of a book on Javascript. You should register your interest for Underhanded Javascript, Or: How to be a Complete Arsehole with Bad Javascript (there’s an alternate title that I’m considering: Javascript Technical Interview Questions). Here’s a quick blurb of the book: [Read More]

I installed OpenCV in a Vagrant box for a new project. It was a pain in the arse. The basic box I used was Official Ubuntu 13.10 daily Cloud Image amd64. After many trials and errors, these are things to note when installing OpenCV in a Vagrant box: Build without GPU and OpenCL When building, don’t build with GPU options: cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local -D WITH_TBB=ON -D BUILD_NEW_PYTHON_SUPPORT=ON -D WITH_QT=ON -D BUILD_opencv_gpu=OFF -D BUILD_opencv_ocl=OFF . [Read More]