PHP

Wrap Around Increments

21st June 2020
Something I've been writing long hand for a number of years is wrap around increments. This is essentially adding to a value that has an upper limit, and wrapping back to 0 when that max value is reached. This can be done with an if statement.

Spelling Words With The Elements

6th June 2020

The other day I was tasked with creating the weekly quiz for my family. I decided it would be good to do a section that would consist of 10 words that were spelled using symbols of the chemical elements. The questions would be presented as a list of element names, like this.

Barium Carbon Potassium Tungsten Argon Darmstadtium

This breaks down to the element symbols in the following way.

Using Deployer To Deploy Drupal 8 Sites

28th April 2020
Deployer is a PHP based deployment tool that I have been using very successfully for a number of months now. It comes with a number of different recipes to deploy a variety of PHP based applications, including Laravel, Symfony, Yii, and Drupal. I first found Deployer when looking for a deployment package that suited my needs. Phing had been my tool of choice for a number of years, but it had proved problematic trying to debug the XML syntax when things needed tweaking. As I was deploying PHP applications it made sense to me to use a PHP based system to do the deployment. I looked at tools like Capistrano, but as I wasn't that familiar with Ruby I was worried that I wouldn't be able to debug mistakes or customise the deployment process easily.

Overwriting Command Line Output With PHP

12th April 2020
The other day I was trying to print some output to the command line and then overwrite the output afterwards. It turns out that there are a couple of ways to do this so I thought I would detail a few of them here. By far the simplest way of doing this is to run the "clear" command, which we can run via the system() function in PHP. This will clear the output of the command line ready for you to print out whatever you need. The downside to this is that the entire terminal window is cleared. Another downside is that once the output is complete scrolling up will reveal the output that was cleared out.

Conway's Game Of Life In PHP

12th April 2020

I was saddened to hear of the passing of the Mathematician John Horton Conway today so I decided to put together a post on his 'game of life' simulator.

This game of life, more commonly called Conway's game of life, was devised by John Conway in 1970 and is a way of modelling very simple cell population dynamics. The game takes place on a two dimensional board containing a grid of orthogonal cells. The game is technically a zero player game in that the initial setup of the game dictates the eventual evolution of the board.

Inverting A Scale

23rd February 2020

One technique I find useful, especially when drawing images, is to invert a number on a scale. In PHP, coordinates in an image are drawn from the top left of the image. This means that if we want to draw from the bottom left then we need to invert the y coordinate.

The following is example PHP code that creates an image with a single, diagonal line, drawn across the middle.

Traits Versus Inheritance In PHP

9th February 2020

The other day I was conducting a code review and found that a developer had used a trait to give two classes the same group of utility methods. Whilst there was nothing wrong with this in terms of functionality, I asked the developer why they had chosen to use traits instead of inheritance. We eventually decided that an inheritance model would be better suited to the situation but I thought I would go through some of the thought processes here.

What Is A Trait?

PHP Custom Stream Filters

29th December 2019
Stream filters allow changes to be made to textual data in streams. This allows text to be changed when writing to or reading from streams, instead of changing the text after the stream has been run. There is a framework built into PHP that allows custom filters to be added to the group of built in filters.

PHP Custom Stream Wrappers

24th December 2019
Part of the strength of PHP's stream wrappers is the ability to add our own stream wrappers to the list of available wrappers. We can therefore natively open any type of resource just by registering a stream wrapper and then using the normal fopen() functions. The custom stream wrapper functionality is made possible through a few functions built into PHP.

PHP Streams

13th December 2019

Streams are a way of generalising file, network, compression resources and a few other things in a way that allows them to share a common set of features. I stream is a resource object that has streamable behaviour. It can be read or written to in a linear fashion, but not necessarily from the beginning of the stream.