@foo{ qw/a b c/ }++ on an empty %foo, will have $foo{a} be 1 and $foo{b} and $foo{c} be undef. That's no problem, because it's only being used for exists. You can have $foo{a} be undef too, by assigning an empty list to the hash splice: @foo{ qw/a b c/ } = ()

By the way, think about these:

<style> span.blah { background-color: expression(alert('Hello, World!'
+)) } </style>
<a href="javascript:alert('Hello, World!');">hi mom</a>
<img src="fourohfour" onerror="alert('Hello, World!');">
[download]

It may be better to define what IS allowed, instead of what's NOT. HTML changes continuously, and browsers don't always follow specs...

For the quotes: just use HTML::Entities, and have it change double quotes to ", zo you can safely use double quotes.

2;0 juerd@ouranos:~$ perl -e'undef christmas'
Segmentation fault
2;139 juerd@ouranos:~$
[download]

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Titles consisting of a single word are discouraged, and in most cases are disallowed outright.

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.