[perl5.git] / ext / Opcode / ops.pm

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
Commit	Line	Data
6badd1a5	1	package ops;
	2
	3	use Opcode qw(opmask_add opset invert_opset);
	4
	5	sub import {
	6	shift;
	7	# Not that unimport is the prefered form since import's don't
	8	# accumulate well owing to the 'only ever add opmask' rule.
	9	# E.g., perl -Mops=:set1 -Mops=:setb is unlikely to do as expected.
2ea6c7ce	10	opmask_add(invert_opset opset(@_)) if @_;
6badd1a5	11	}
	12
	13	sub unimport {
	14	shift;
2ea6c7ce	15	opmask_add(opset(@_)) if @_;
6badd1a5	16	}
	17
	18	1;
	19
	20	__END__
	21
	22	=head1 NAME
	23
	24	ops - Perl pragma to restrict unsafe operations when compiling
	25
	26	=head1 SYNOPSIS
	27
	28	perl -Mops=:default ... # only allow reasonably safe operations
	29
	30	perl -M-ops=system ... # disable the 'system' opcode
	31
	32	=head1 DESCRIPTION
	33
f610777f	34	Since the ops pragma currently has an irreversible global effect, it is
6badd1a5	35	only of significant practical use with the C<-M> option on the command line.
	36
	37	See the L<Opcode> module for information about opcodes, optags, opmasks
	38	and important information about safety.
	39
	40	=head1 SEE ALSO
	41
	42	Opcode(3), Safe(3), perlrun(3)
	43
	44	=cut
	45