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and rewrite "use $package;" to "use @{[__PACKAGE__]}::$package;" of script "$0".
END
}

# P.302 Module Privacy and the Exporter
# in Chapter 11: Modules
# of ISBN 0-596-00027-8 Programming Perl Third Edition.
#
# A module can do anything it jolly well pleases when it's used, since use just
# calls the ordinary import method for the module, and you can define that
# method to do anything you like.

# P.406 Module Privacy and the Exporter
# in Chapter 11: Modules
# of ISBN 978-0-596-00492-7 Programming Perl 4th Edition.
#
# A module can do anything it jolly well pleases when it's used, since use just
# calls the ordinary import method for the module, and you can define that
# method to do anything you like.

sub import {

    if (-e("$filename.e")) {
        if (exists $ENV{'CHAR_DEBUG'}) {
            unlink "$filename.e";
        }
        elsif (-z("$filename.e")) {
            unlink "$filename.e";
        }
        else {

            #----------------------------------------------------
            #  older >
            #  newer >>>>>
            #----------------------------------------------------
            # Filter >
            # Source >>>>>
            # Escape >>>   needs re-escape (Source was changed)
            #
            # Filter >>>
            # Source >>>>>
            # Escape >     needs re-escape (Source was changed)
            #
            # Filter >>>>>
            # Source >>>
            # Escape >     needs re-escape (Source was changed)
            #
            # Filter >>>>>
            # Source >
            # Escape >>>   needs re-escape (Filter was changed)
            #
            # Filter >
            # Source >>>
            # Escape >>>>> executable without re-escape
            #
            # Filter >>>
            # Source >
            # Escape >>>>> executable without re-escape
            #----------------------------------------------------

            my $mtime_filter = (stat(__FILE__     ))[9];
            my $mtime_source = (stat($filename    ))[9];
            my $mtime_escape = (stat("$filename.e"))[9];
            if (($mtime_escape < $mtime_source) or ($mtime_escape < $mtime_filter)) {
                unlink "$filename.e";
            }
        }
    }

    if (not -e("$filename.e")) {
        my $fh = gensym();
        Eutf2::_open_a($fh, "$filename.e") or die __FILE__, ": Can't write open file: $filename.e\n";

        # 7.19. Flushing Output
        # in Chapter 7. File Access
        # of ISBN 0-596-00313-7 Perl Cookbook, 2nd Edition.

        select((select($fh), $|=1)[0]);

        if (0) {
        }
        elsif (exists $ENV{'CHAR_NONBLOCK'}) {

            # P.419 File Locking
            # in Chapter 16: Interprocess Communication
            # of ISBN 0-596-00027-8 Programming Perl Third Edition.

            # P.524 File Locking
            # in Chapter 15: Interprocess Communication
            # of ISBN 978-0-596-00492-7 Programming Perl 4th Edition.

            # P.571 Handling Race Conditions
            # in Chapter 23: Security
            # of ISBN 0-596-00027-8 Programming Perl Third Edition.

            # P.663 Handling Race Conditions
            # in Chapter 20: Security
            # of ISBN 978-0-596-00492-7 Programming Perl 4th Edition.

            # (and so on)

            CORE::eval q{ flock($fh, LOCK_EX | LOCK_NB) };
            if ($@) {
                die __FILE__, ": Can't immediately write-lock the file: $filename.e\n";
            }
        }
        else {
            CORE::eval q{ flock($fh, LOCK_EX) };
        }

        CORE::eval q{ truncate($fh, 0) };
        seek($fh, 0, 0) or die __FILE__, ": Can't seek file: $filename.e\n";

        my $e_script = UTF2::escape_script($filename);
        print {$fh} $e_script;

        my $mode = (stat($filename))[2] & 0777;
        chmod $mode, "$filename.e";

        close($fh) or die "Can't close file: $filename.e: $!";
    }

    my $fh = gensym();
    Eutf2::_open_r($fh, "$filename.e") or die __FILE__, ": Can't read open file: $filename.e\n";

    if (0) {
    }
    elsif (exists $ENV{'CHAR_NONBLOCK'}) {
        CORE::eval q{ flock($fh, LOCK_SH | LOCK_NB) };
        if ($@) {
            die __FILE__, ": Can't immediately read-lock the file: $filename.e\n";
        }
    }
    else {
        CORE::eval q{ flock($fh, LOCK_SH) };
    }

    my @switch = ();
    if ($^W) {
        push @switch, '-w';
    }
    if (defined $^I) {
        push @switch, '-i' . $^I;
        undef $^I;
    }

    # P.707 29.2.33. exec
    # in Chapter 29: Functions
    # of ISBN 0-596-00027-8 Programming Perl Third Edition.
    #
    # If there is more than one argument in LIST, or if LIST is an array with more
    # than one value, the system shell will never be used. This also bypasses any
    # shell processing of the command. The presence or absence of metacharacters in
    # the arguments doesn't affect this list-triggered behavior, which makes it the
    # preferred from in security-conscious programs that do not with to expose
    # themselves to potential shell escapes.
    # Environment variable PERL5SHELL(Microsoft ports only) will never be used, too.

    # P.855 exec
    # in Chapter 27: Functions
    # of ISBN 978-0-596-00492-7 Programming Perl 4th Edition.
    #
    # If there is more than one argument in LIST, or if LIST is an array with more
    # than one value, the system shell will never be used. This also bypasses any
    # shell processing of the command. The presence or absence of metacharacters in
    # the arguments doesn't affect this list-triggered behavior, which makes it the
    # preferred from in security-conscious programs that do not wish to expose
    # themselves to injection attacks via shell escapes.
    # Environment variable PERL5SHELL(Microsoft ports only) will never be used, too.

    # P.489 #! and Quoting on Non-Unix Systems
    # in Chapter 19: The Command-Line Interface
    # of ISBN 0-596-00027-8 Programming Perl Third Edition.

    # P.578 #! and Quoting on Non-Unix Systems
    # in Chapter 17: The Command-Line Interface
    # of ISBN 978-0-596-00492-7 Programming Perl 4th Edition.