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+package ops;
+
+our $VERSION = '1.02';
+
+use Opcode qw(opmask_add opset invert_opset);
+
+sub import {
+ shift;
+ # Not that unimport is the preferred 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 C<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
+
+L<Opcode>, L<Safe>, L<perlrun>
+
+=cut
+