What's so wrong with doing open RD, '<', 'file.txt' ?

I was involved with two discussions about this recently, lexical vs. local file handles and Re^2: Summing numbers in a file, so here are my two cents. To summarize the disadvantages of bareword filehandles:

• They don't protect against typos.
• They're package-globals.
• They clash with package names and subs.
• If you do want to localize them, that comes with even more disadvantages.
• Package-global filehandles usually go out of scope much later than lexicals, so the automatic close doesn't really help.

I don't think that bareword filehandles should "never, ever" be used, and removing them would most likely break a lot of CPAN. But IMHO they shouldn't be used in new code, and newcomers should use lexicals instead. My understanding of Perl 7 is that it is an attempt to introduce defaults that are modern and reduce the cognitive load on the coder - sure, you can use bareword filehandles if you know what you're doing and are willing to manually check for all potentially typos and name clashes caused by them. In the beginning, I used to code without strict and warnings, and I can still remember the amount of time I would spend proofreading my code for such issues.

use of barewords as filehandles will be disallowed in perl 7

My understanding of Sawyer's talk is that the new default will be no bareword::filehandles, and you are free to write use bareword::filehandles.

---

---

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.