I was recently shown this puzzle: There are some things I found a little unclear about it. For example, should the following two circles count as being connected? There is a line between them, even if it’s interrupted by a circle. And what about these two circles? Are they connected? Again, there’s a diagonal line … Continued
In class-based object-oriented programming, when there are classes that appear to share some functionality, this is often a time when people will refactor them into two subclasses of a common base class, avoiding repetition.
For example, in my farm model the Horse class and the Tractor class each implement a pull_plough method. (American readers might prefer pull_plow.) So this method is a candidate to split out into a Hitchable class for Horse and Tractor to each inherit from.
This would have nice benefits for polymorphism. I’ll be able to pass an object to my Farmer which will only need to check that the object inherits from Hitchable rather than having a hard-coded list of classes like Horse and Tractor that it knows are acceptable.
Tonight I've released another alpha version of Cognition, my semantic web parser. Changelog includes: Microformats: Add option (disabled by default) to require <head profile> for microformat support. Microformat profiles are treated as opaque strings! Supports the following profiles: http://purl.org/uF/2008/03/ http://www.w3.org/2006/03/hcard or http://purl.org/uF/hCard/1.0/ http://dannyayers.com/microformats/hcalendar-profile or http://purl.org/uF/hCalendar/1.0/ http://purl.org/uF/hAtom/0.1/ http://purl.org/uF/rel-tag/1.0/ http://purl.org/uF/rel-license/1.0/ No profiles required for rel-enclosure, adr or … Continued
I’ve searched around the ‘Net for something like this before, but without success, so decided to write my own. The basic idea is this: there are certain circumstances in which you need to write some styled HTML without access to the document’s header. For example, when composing HTML-formatted e-mails, which may be displayed in a … Continued
Here’s my latest update to dhyana.pl… Change Log Added a title to the output image, which can be in a different font and colour from the rest of the text. Use Getopt to parse command line, and accept more options. Improved handling of certain dodgy WMV files, mostly thanks to Matt Pinkham. Improved use of … Continued
This release works around errors in capturing screen shots from certain WMV files. It also changes the default geometry from 240Ã180+0+0 to “auto” which is an automatically calculated, hopefully appropriate, geometry. Download dhyana.pl Highlighted source code
So, I was looking for a way to create sequential video thumbnails (like this one) from a video file on Linux. I found that my options were severely limited. On Windows there are a plethora of tools capable of this fairly simple task, including Media Player Classic, but on Linux all I could find was … Continued
PHP lets you define your own error handler, so I decided to get a bit fancy. MegaErrorHandler (MEH) outputs its errors as specially-formatted HTML comments, with the details of the error encoded using JSON. A small client-side script, with an associated stylesheet then pulls this data out of the comments and formats it as a … Continued
Here’s an example of how to parse an HTML table into an array using the PEAR module XML_HTMLSax3. It supports the , and elements and the rowspan and colspan attributes. It’s worth noting that this code will raise a bunch of notices if you run it displaying all errors. This is pretty difficult to avoid, … Continued
On Usenet an often-asked question is how to programmatically determine the “domain” of a particular hostname. That is, excluding the components traditionally thought of as subdomains. As an example, groups.google.com and www.google.com both have a domain of google.com. Invariably, one answer comes back stating that you just need to chop off everything from the front, … Continued
Here's a simple program which calculates, to eight decimal places, the value of the Golden Ratio φ implemented in both PHP and Perl, to demonstrate their similarities. Perl #!/usr/bin/perl $a = 1; $b = 1; $c = undef; $psi_old = undef; print “Approximating psi…\n”; while (1) { $psi = sprintf(‘%.08f’, $b/$a); last if ($psi_old eq … Continued
Here’s a PHP function for reformatting the whitespace in PHP code:
Most programmers, especially those who work on server software, will have been in a situation when we’ve been reconfiguring, upgrading, modifying or otherwise replacing some piece of vital software on a physically remote server, and things haven’t gone quite as expected. Often, fixing it is a simple matter of logging into the server remotely (via, … Continued
I put this together back in January 2006, but never mentioned it on my website — I just posted it on a couple of newsgroups. It’s pretty good fun and rather realistic. Create your own Dan Brown novel
Firstly, three disclaimers: PHP is a great programming language, one of my favourites — this website is written in PHP; there are many great PHP programmers out there, some of whom probably never get things wrong; I probably get things wrong a lot of the time. The majority of the database-backed Open Source PHP projects … Continued
At last, my new CMS is at a stage when I’m able to actually start publishing with it. Now that I have an easy-ish tool to publish with, you can expect that this website will be updated more frequently and with more and better content. Updating this website in the past has been a major … Continued
Tyno Gendo wrote: I have been pondering over building a “modular” site which accepts add-ons built by other people. I was wondering if anyone has any links to any reading material on how you build this kind of facility into your site? The basic technique is this: Firstly, provide a plugin registration function, which we’ll … Continued
Michael Fesser wrote: My scripts make use of many of the new OOP features in PHP 5, so they won’t run at all on PHP 4. Ditto. My current big pet project is http://demiblog.org/. This is PHP 5+ only and supports MySQL 5+ and PostgreSQL 8+. Although I do realise that earlier versions of these … Continued
skulkrinbait@googlemail.com wrote: My first prototype for doing this doesn’t give good results, the map being far too random, can someone help me out or point me to a good resource please? Real geography is not random. First, take a grid, say 1001Ã1001 is size. Now find the middle square of it and set it to … Continued
cjl wrote: Short of writing a parser, which is clearly beyond me, what are some reasonable approaches to handling user input that will be executed? Writing a parser is the best option in the long-run. If you were to attempt to interpret the user input some other way, like pure regular expressions, then you would … Continued
