package strict;
+$strict::VERSION = "1.02";
+
+my %bitmask = (
+refs => 0x00000002,
+subs => 0x00000200,
+vars => 0x00000400
+);
+
+sub bits {
+ my $bits = 0;
+ my @wrong;
+ foreach my $s (@_) {
+ push @wrong, $s unless exists $bitmask{$s};
+ $bits |= $bitmask{$s} || 0;
+ }
+ if (@wrong) {
+ require Carp;
+ Carp::croak("Unknown 'strict' tag(s) '@wrong'");
+ }
+ $bits;
+}
+
+sub import {
+ shift;
+ $^H |= bits(@_ ? @_ : qw(refs subs vars));
+}
+
+sub unimport {
+ shift;
+ $^H &= ~ bits(@_ ? @_ : qw(refs subs vars));
+}
+
+1;
+__END__
+
=head1 NAME
strict - Perl pragma to restrict unsafe constructs
print $$ref; # ok
$ref = "foo";
print $$ref; # runtime error; normally ok
+ $file = "STDOUT";
+ print $file "Hi!"; # error; note: no comma after $file
+
+There is one exception to this rule:
+
+ $bar = \&{'foo'};
+ &$bar;
+
+is allowed so that C<goto &$AUTOLOAD> would not break under stricture.
+
=item C<strict vars>
This generates a compile-time error if you access a variable that wasn't
-declared via C<use vars>,
-localized via C<my()> or wasn't fully qualified. Because this is to avoid
+declared via "our" or C<use vars>,
+localized via C<my()>, or wasn't fully qualified. Because this is to avoid
variable suicide problems and subtle dynamic scoping issues, a merely
local() variable isn't good enough. See L<perlfunc/my> and
L<perlfunc/local>.
local $foo = 9; # blows up
package Cinna;
- use vars qw/ $bar /; # Declares $bar in current package
+ our $bar; # Declares $bar in current package
$bar = 'HgS'; # ok, global declared via pragma
The local() generated a compile-time error because you just touched a global
name without fully qualifying it.
+Because of their special use by sort(), the variables $a and $b are
+exempted from this check.
+
=item C<strict subs>
This disables the poetry optimization, generating a compile-time error if
=back
-See L<perlmod/Pragmatic Modules>.
-
+See L<perlmodlib/Pragmatic Modules>.
=cut
-
-$strict::VERSION = "1.01";
-
-my %bitmask = (
-refs => 0x00000002,
-subs => 0x00000200,
-vars => 0x00000400
-);
-
-$strict::VERSION = "1.01";
-
-my %bitmask = (
-refs => 0x00000002,
-subs => 0x00000200,
-vars => 0x00000400
-);
-
-sub bits {
- my $bits = 0;
- foreach my $s (@_){ $bits |= $bitmask{$s} || 0; };
- $bits;
-}
-
-sub import {
- shift;
- $^H |= bits(@_ ? @_ : qw(refs subs vars));
-}
-
-sub unimport {
- shift;
- $^H &= ~ bits(@_ ? @_ : qw(refs subs vars));
-}
-
-1;