package App::Tasker::SafeExec;

sub _onmatch_fail
{
    my ( $_codetext, $_valhref, $_taskname ) = @_;

    $_codetext .= "# line 1 task[$_taskname]\n" . $_codetext;

    {
        use Safe;
        my $_compartment = new Safe;

        our $FAIL_MATCH = 0;    # match defaults to succeed
        my $_epilog   = '';
        my $_newval   = {};
        my $_evaltext = <<'EOT';
$_compartment->share('$FAIL_MATCH');
EOT
        while ( my ( $k, $v ) = each %$_valhref )
        {
            $_evaltext .= <<EOT;
our \$$k = '$v';
\$_compartment->share('\$$k');
EOT

            $_epilog .= <<EOT;
\$_newval->{'$k'} = \$$k;
EOT
        }

        $_evaltext .= <<'EOT';
$_compartment->reval($_codetext, 1);
die $@ if $@;
EOT
        $_evaltext .= $_epilog;

        eval $_evaltext;
        die $@ if $@;

        for my $k ( keys %$_valhref )
        {
            $_valhref->{$k} = $_newval->{$k};
        }

        return $FAIL_MATCH;
    }
}