While cleaning Tiny Applications Collection a little I’ve dropped both artificial intelligence scripts. However, not wanting to let them disappear, I’ve decided to post them here for posterity.

The first one is an eight line of code version that might be what Sid wrote as his first program ever:

#!/usr/bin/perl -wWtT
while (<>) {
	if (/[aeiouyAEIOUY][^a-zA-Z]*$/) {
		print "Yes.\n";
	} elsif (!/^\s*$/) {
		print "No.\n";
	}
}

The second one is an ‘improved’ six-line version akin to Pitr’s code:

#!/usr/bin/perl -wWtTn
if (/[aeiouyAEIOUY][^a-zA-Z]*$/) {
	print "No!\n";
} elsif (!/^\s*$/) {
	print "Yes.\n";
}

HTML has gone quite a long way since its inception. This means a lot of new features but also some small incompatibilities which may pose issues in certain situations. For instance, when posting a code snippet for others to include on their websites, it’s best if it works correctly on as many sites as possible which implies being compatible with as many versions of HTML as possible. But how to create a snippet that works both in HTML and XHTML? Here are a few tips:

CSS sprites aren’t anything new. They have been around for years, and are one of the methods to optimise website’s load time. The idea is to incorporate multiple images into one and in this way decrease number of round trips between the server and the browser.

In its traditional use, CSS sprites work as a replacement for images and cannot be used as a background. Alas that is exactly what I wanted to do with a quote and flag icons like the following:

Update: This website has evolved slightly since 2013. The flags are no longer used (replaced by content negotiation) and quote sprite icon has been replaced by an SVG. While I no longer use this technique, it is of course still valid.

After some playing around I’ve finally figured out how to get this working. Even though there are some caveats, sprites can be used as a top-left no-repeat background image as well.

Surprisingly I couldn’t find any HTTPS-aware examples how to drop the www. prefix from web hosts in Apache, so I had to come up with one myself. Firstly, the following lines need to find their way to the end of Apache configuration file (/etc/httpd/conf/httpd.conf or something):

RewriteEngine on
RewriteCond %{HTTPS} off
RewriteCond %{HTTP_HOST} ^www\.(.*)$
RewriteRule ^(.*)$ http://%1$1 [L,R=301]

Secondly, analogous lines need to be added inside of the <VirtualHost _default_:443> directive of mod_ssl configuration file (/etc/httpd/conf.d/ssl.conf or similar), like so:

<VirtualHost _default_:443>
	# … various directives …

	# Here’s what needs to be added:
	RewriteEngine on
	RewriteCond %{HTTP_HOST} ^www\.(.*)$
	RewriteRule ^(.*)$ https://%1$1 [L,R=301]
</VirtualHost>

Now, after a restart, Apache will drop the www. prefix for both secure and insecure connections.