Thus if you say:

perl -lwe 'sub our { print shift } $foo = "bar"; our $foo'
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The 'our' keyword has not had any function prior to perl5.6 (unless you count experimental versions that is).

But why did they have to tell us not to use 'our' ? Well, take a look at that code again. In perl prior to 5.6 it prints "bar" (and may give you the warning) - in perl5.6 it doesn't print anything out because you now declare the $foo variable rather than sending it to a function called 'our'.

Autark

'our' has been reserved in versions earlier than 5.6.0. Saying it's deprecated is likely just bad wording. In 5.6.0, the 'our' keyword is synonymous with 'use vars' to declare package globals. This is AFAIK (one of the 5.005* perldelta pages, i believe, mentions that 'our' has been reserved).

local $_ = "0A72656B636148206C72655020726568746F6E41207473754A";
while(s/..$//) { print chr(hex($&)) }
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In 5.6.0, the 'our' keyword is synonymous with 'use vars' to declare package globals.

Uh, no. Not quite. It's use vars but with lexical scoping, so if it's inside a block, it loses effect after the block.

-- Randal L. Schwartz, Perl hacker

No, saying "use of reserved word XXX is deprecated" is a very proper message; you're using a bareword, and Perl is letting you know you shouldn't, since it's reserved for a future use. Perl didn't say "use of XXX is deprecated."

$_="goto+F.print+chop;\n=yhpaj";F1:eval

Okay, I consider myself a fairly advanced Perl programmer (after over a dozen years of it), but I find that distinction pretty danged subtle. I'd say the message "use of reserved word XXX is deprecated" is very poorly worded. It very much sounds like "use of XXX is deprecated, and, by the way, it is a reserved word".

The existence of perldiag.pod helps relieve this problem (it says "Future versions of perl may use it as a keyword..." for this message).

But it is still terrible because the meaning of "reserved word" in C (the only other place I've heard that term) is "a word reserved for use by the language", that is "if", "else", "goto", etc. So a "reserved word" in C is the same as a "keyword" in Perl.

It is strange that Perl, a language that takes much from C, to use C's phrase for "keyword" as Perl's phrase for "not yet a keyword".

In fact, I just did some checking of my facts, and I found the use of the term "reserved word" for what Perl calls "keyword" in several places other than C. In fact, Perl uses the term "reserved word" to include current keywords (see perldata.pod) so to say "'our' is a reserved word" doesn't even tell you that "our" isn't currently a keyword.

A much better error message would be "The bareword XXX may become a Perl keyword, please quote it". *sigh*, now I have a moral obligation to submit a patch. :)

OK. </rant>