I've written an application which parses RSS feeds and outputs a Web page so I can track changes on my favourite sites. There's nothing original or exciting about that.

I discovered that several sites I'm interested in sometimes output badly formed RSS. Special characters are often unescaped, which causes problems for XML::RSS and any other strict XML parser.

I've written a simple heuristic to parse badly formed XML, which might be of use to others. Maybe you can help me improve this? 

use XML::RSS ();
my $rss_content = "RSS goes here";

my @replace = (
    ['\&(\s)', '"&$1"'], # '&' followed by space
    ['(\s)>',  '"$1>"'],   # '>' with preceding space
    ['\&',     '"&"'],   # All '&'
);
my($data, $rss);
PARSE: while (my $repl = shift @replace) {
    $rss = XML::RSS->new;
    $data = eval { $rss->parse($rss_content) } and last PARSE;
} continue {
    $content =~ s/$repl->[0]/eval($repl->[1])/ge;
}
die unless $data;

[download]

I've only used this with XML::RSS, but this technique could be applied to XML::Parser, or any other XML parsing code.

In reply to Parsing badly formed RSS or XML by tomhukins

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