Blog time zone moved to UTC
I have just moved to a different country with different time zone. In the past, my server and my blogs were all placed in my local time. Now they can be confusing as I can manage my server from different locations, and…
Confusion between the term “reference” and “pointer”
A few years ago, I wrote an article saying that Java has pointers. However, by typing Java pointer into Google, there are a lot of Stack Exchange questions shown on the top, some says Java does not have pointers, some says Java…
Personal blog was cracked today
Today when I tried to open one of my websites https://longswims.net/ in order to update its contents, it stopped working throwing HTTP 500. I immediately signed in the web server and found out that the .php file was injected unknown code. I…
Citybus & NWFB combined ETA released
I have made a web app to show Citybus & NWFB combined ETA, which was released last month. It has two distinguishing features which bring convenience to users (including myself): It can show the first 3 upcoming departures for any combination of…
Hong Kong OpenTripPlanner instance up
The government of Hong Kong has released public transport data set as GTFS. In response, I have built an OpenTripPlanner instance to work on those data as an experiment to have 100% open data public transport routing. The instance is currently accessible…
Type-safe callables in PHP by interfaces with __invoke()
The type system in PHP has become safer each version since PHP 7.0, by using a strict type declaration on top of the PHP file. As a newly-developed feature, it doesn’t come with the billion-dollar mistake of allowing NULL for variables declared…
Personal website completely modernised
I started building my own website in 2008 when I was still in secondary school using PHP and (X)HTML. At that time, the PHP version was only 5.2, without modern features like namespaces, late static bindings, closures, type safety, etc. There was…
static in depth
After my previous post about static members in various programming language, I decide to write a post about the word static in depth. static is a key word in multiple programming languages, with multiple distinct but related meanings. The history The static…
static in PHP
static keyword is used to represent class members, i.e. members which are shared among the class, as opposed of instance members which is unique to an object instance, in many programming languages, including PHP. However, the static functionality in PHP is much…
The philosophy of nothing
Nothing, the opposite of something, does not exist. To represent something is trivial, but, how we can represent nothing is a great philosophical problem. What is nothing? Even when put in the context of application, the concept of nothing may not be…