1. Never heard about such docs. Anyway in my experience perldeltas are not sufficient. I have quite good understanding of what is allowed in old Perls but still I've biten a couple of times by bugs in old Perls. I.e. being developing on 5.6.1 and using 5.005 supported syntax I found my code to don't work on 5.005 because of bugs in this version. The only way to ensure compatibility is having 100% coverage tests and run them on all supported versions of Perl.
2. I think most Linux distros have 5.6.1, FreeBSD still at 5.005 (though it is possible to get 5.6.1 from port). Commercial Unices are very conservative. I've heard some of them still bundle Perl 4! So I think most their users install Perl themselves anyway.
3. Really depends on your target audience. If it is your internal project to be used in, say, inside your company than it probably is not hard to require specific version. On the other hand company I'm working for right now has a Perl project our customer explictly requires 5.004 (!) compatiblity. Shortly speaking it is a plugin for customer's shopping cart targeted for wide audience. When I've beeing discussed Perl version requirements for this software they said they still have a lot of support calls from users with this version of Perl. Requiring even 5.005 means lost money.

--
Ilya Martynov (http://martynov.org/)

---

---

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.