windows-nt/Source/XPSP1/NT/tools/x86/perl/lib/ops.pm
2020-09-26 16:20:57 +08:00

46 lines
969 B
Perl

package ops;
use Opcode qw(opmask_add opset invert_opset);
sub import {
shift;
# Not that unimport is the prefered form since import's don't
# accumulate well owing to the 'only ever add opmask' rule.
# E.g., perl -Mops=:set1 -Mops=:setb is unlikely to do as expected.
opmask_add(invert_opset opset(@_)) if @_;
}
sub unimport {
shift;
opmask_add(opset(@_)) if @_;
}
1;
__END__
=head1 NAME
ops - Perl pragma to restrict unsafe operations when compiling
=head1 SYNOPSIS
perl -Mops=:default ... # only allow reasonably safe operations
perl -M-ops=system ... # disable the 'system' opcode
=head1 DESCRIPTION
Since the ops pragma currently has an irreversible global effect, it is
only of significant practical use with the C<-M> option on the command line.
See the L<Opcode> module for information about opcodes, optags, opmasks
and important information about safety.
=head1 SEE ALSO
Opcode(3), Safe(3), perlrun(3)
=cut