package vars;
+require 5.002;
+
+our $VERSION = '1.00';
+
+# The following require can't be removed during maintenance
+# releases, sadly, because of the risk of buggy code that does
+# require Carp; Carp::croak "..."; without brackets dying
+# if Carp hasn't been loaded in earlier compile time. :-(
+# We'll let those bugs get found on the development track.
+require Carp if $] < 5.00450;
+
+use warnings::register;
+require strict;
+
+sub import {
+ my $callpack = caller;
+ my ($pack, @imports, $sym, $ch) = @_;
+ foreach $sym (@imports) {
+ ($ch, $sym) = unpack('a1a*', $sym);
+ if ($sym =~ tr/A-Za-z_0-9//c) {
+ # time for a more-detailed check-up
+ if ($sym =~ /::/) {
+ require Carp;
+ Carp::croak("Can't declare another package's variables");
+ } elsif ($sym =~ /^\w+[[{].*[]}]$/) {
+ require Carp;
+ Carp::croak("Can't declare individual elements of hash or array");
+ } elsif (warnings::enabled() and length($sym) == 1 and $sym !~ tr/a-zA-Z//) {
+ warnings::warn("No need to declare built-in vars");
+ } elsif ( $^H &= strict::bits('vars') ) {
+ Carp::croak("'$ch$sym' is not a valid variable name under strict vars");
+ }
+ }
+ *{"${callpack}::$sym"} =
+ ( $ch eq "\$" ? \$ {"${callpack}::$sym"}
+ : $ch eq "\@" ? \@ {"${callpack}::$sym"}
+ : $ch eq "\%" ? \% {"${callpack}::$sym"}
+ : $ch eq "\*" ? \* {"${callpack}::$sym"}
+ : $ch eq "\&" ? \& {"${callpack}::$sym"}
+ : do {
+ require Carp;
+ Carp::croak("'$ch$sym' is not a valid variable name");
+ });
+ }
+};
+
+1;
+__END__
+
=head1 NAME
-vars - Perl pragma to predeclare global variable names
+vars - Perl pragma to predeclare global variable names (obsolete)
=head1 SYNOPSIS
=head1 DESCRIPTION
+NOTE: The functionality provided by this pragma has been superseded
+by C<our> declarations, available in Perl v5.6.0 or later. See
+L<perlfunc/our>.
+
This will predeclare all the variables whose names are
in the list, allowing you to use them under "use strict", and
disabling any typo warnings.
for the entire file in which they appear. You may not rescind such
declarations with C<no vars> or C<no subs>.
-Packages such as the B<AutoLoader> and B<SelfLoader> that delay loading
-of subroutines within packages can create problems with package lexicals
-defined using C<my()>. While the B<vars> pragma cannot duplicate the
-effect of package lexicals (total transparency outside of the package),
-it can act as an acceptable substitute by pre-declaring global symbols,
-ensuring their availability to to the later-loaded routines.
+Packages such as the B<AutoLoader> and B<SelfLoader> that delay
+loading of subroutines within packages can create problems with
+package lexicals defined using C<my()>. While the B<vars> pragma
+cannot duplicate the effect of package lexicals (total transparency
+outside of the package), it can act as an acceptable substitute by
+pre-declaring global symbols, ensuring their availability to the
+later-loaded routines.
-See L<perlmod/Pragmatic Modules>.
+See L<perlmodlib/Pragmatic Modules>.
=cut
-require 5.000;
-use Carp;
-
-sub import {
- my $callpack = caller;
- my ($pack, @imports, $sym, $ch) = @_;
- foreach $sym (@imports) {
- croak "Can't declare another package's variables" if $sym =~ /::/;
- ($ch, $sym) = unpack('a1a*', $sym);
- *{"${callpack}::$sym"} =
- ( $ch eq "\$" ? \$ {"${callpack}::$sym"}
- : $ch eq "\@" ? \@ {"${callpack}::$sym"}
- : $ch eq "\%" ? \% {"${callpack}::$sym"}
- : $ch eq "\*" ? \* {"${callpack}::$sym"}
- : $ch eq "\&" ? \& {"${callpack}::$sym"}
- : croak "'$ch$sym' is not a valid variable name\n");
- }
-};
-
-1;