I recently made a little script to come up with an index for the increasingly unwieldy Name Space thread. This led me into an area I've not explored before (one of many, I hasten to add), that of extracting info from HTML. I wanted something that wd go through the page and pull out a node number and name for the first post by each monk who had contributed to the thread. What I came up with was this:
#!/usr/bin/perl -w
use strict;
use CGI qw(:standard :cgi-lib);
use LWP::Simple;
my $url ="http://perlmonks.org/index.pl?node_id=110166";
my $html = get $url or die "can't get url $!";
my %names;
#find the names and node ids:
while ($html =~ s/=(\d*?)&lastnode_id=110166">[^<]*<\/A><BR> by <A HRE
+F="\/index\.pl\?node_id=\d*&lastnode_id=110166">(.*?)<\/A> on \w{3} \
+d{2}, \d{4} at \d{2}:\d{2}//s) {
$names{$2} = $1 unless $names{$2};
}
# print out a page of links to nodes:
for (sort { lc($a) cmp lc($b) } keys %names) {
print "<A HREF=\"/index.pl?node_id=$names{$_}&lastnode_id=110166\"
+>$_</A> | ";
}
... which does the job, BUT the regex is big and fat and ugly, and I just wondered whether there was a more elegant, less impenetrable way to do it (i.e. I wondered how *many* such ways there were). I looked at HTML::Parser, but (and perhaps my inspection was too cursory) it didn't seem as though it wd help me much in pulling out bits of tags, as I need to here. Also, I felt that the while loop was a bit clumsy... but couldn't see a quicker way to capture two matches into a hash. I'd be very interested in any suggestions how to do this better.
§ George Sherston
Edit: chipmunk 2001-11-11
-
Are you posting in the right place? Check out Where do I post X? to know for sure.
-
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big>
<blockquote> <br /> <dd>
<dl> <dt> <em> <font>
<h1> <h2> <h3> <h4>
<h5> <h6> <hr /> <i>
<li> <nbsp> <ol> <p>
<small> <strike> <strong>
<sub> <sup> <table>
<td> <th> <tr> <tt>
<u> <ul>
-
Snippets of code should be wrapped in
<code> tags not
<pre> tags. In fact, <pre>
tags should generally be avoided. If they must
be used, extreme care should be
taken to ensure that their contents do not
have long lines (<70 chars), in order to prevent
horizontal scrolling (and possible janitor
intervention).
-
Want more info? How to link
or How to display code and escape characters
are good places to start.
|