Perl for Web Site Management

Generating the Top-level Page

We’re almost done. All that’s left is to generate the site’s top-level page. Here’s the code that does that:

# write out the top-level page

my $path      = "$base_path/index.html";
my $title     = "$show_name Exhibitor Listings";
my $alpha_bar = &make_alpha_bar;
my $date      = localtime;
my $count     = keys %listing; # how many exhibitors, total?

my $content   = <<"EOF";
<H2 ALIGN="center">$show_name Exhibitor Listings</H2>

<P ALIGN="center"><EM>Last updated $date<BR>
$count exhibitors total</EM></P>

<P><STRONG>Alphabetical Index:</STRONG></P>

$alpha_bar

<P><STRONG>Category Index:</STRONG></P>

<UL>
$cat_list
</UL>
EOF

&write_page($path, $title, $content);

There are just a few new tricks here. First, we make an alpha bar for the top-level page, but we don’t pass the subroutine a letter as an argument, so the alpha bar we get back does not have any unlinked letters.

Next, we populate the $date variable, which we’ll use to put a timestamp on the top-level page, by assigning the output of Perl’s localtime function to it. The localtime function is interesting because it behaves differently depending on whether it is in a scalar or an array context. If you put it in an array context (by assigning its output to an array variable, for example), it will return a list of various elements relating to the current date and time. If you put it in a scalar context, though (as we’ve done here, by assigning its output to a scalar variable), it returns a string describing the current ...