package vars;
+use 5.006;
+
+our $VERSION = '1.03';
+
+use warnings::register;
+use strict qw(vars subs);
+
+sub import {
+ my $callpack = caller;
+ my (undef, @imports) = @_;
+ my ($sym, $ch);
+ foreach (@imports) {
+ if (($ch, $sym) = /^([\$\@\%\*\&])(.+)/) {
+ if ($sym =~ /\W/) {
+ # time for a more-detailed check-up
+ if ($sym =~ /^\w+[[{].*[]}]$/) {
+ 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'))) {
+ require Carp;
+ Carp::croak("'$_' is not a valid variable name under strict vars");
+ }
+ }
+ $sym = "${callpack}::$sym" unless $sym =~ /::/;
+ *$sym =
+ ( $ch eq "\$" ? \$$sym
+ : $ch eq "\@" ? \@$sym
+ : $ch eq "\%" ? \%$sym
+ : $ch eq "\*" ? \*$sym
+ : $ch eq "\&" ? \&$sym
+ : do {
+ require Carp;
+ Carp::croak("'$_' is not a valid variable name");
+ });
+ } else {
+ require Carp;
+ Carp::croak("'$_' is not a valid variable name");
+ }
+ }
+};
+
+1;
+__END__
+
=head1 NAME
vars - Perl pragma to predeclare global variable names
=head1 DESCRIPTION
+NOTE: For use with variables in the current package for a single scope, the
+functionality provided by this pragma has been superseded by C<our>
+declarations, available in Perl v5.6.0 or later, and use of this pragma is
+discouraged. 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 5.002;
-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;