perl – 从标量变量创建VSTRING而不使用eval

I. e.,这有效,但使用eval：

my $var = 'v1.2.3';
my $conversion = to_vstring_1($var);
# Prints "Version: 1.2.3,type: VSTRING"
printf("Version: %vd,type: %sn",$conversion,ref $conversion);

sub to_vstring_1 {
    my ($arg) = @_;

    $arg =~ tr/0-9.//cd;
    $arg = 'v' . $arg;

    return eval $arg;
}

这两个变体也有效,并且不使用eval,但它们打印“SCALAR”而不是“VSTRING”：

my $conversion_2 = to_vstring_2($var);
# Prints "Version: 1.2.3,type: SCALAR"
printf("Version: %vd,$conversion_2,ref $conversion_2);

my $conversion_3 = to_vstring_3($var);
# Prints "Version: 1.2.3,$conversion_3,ref $conversion_3);

sub to_vstring_2 {
    my ($arg) = @_;

    $arg =~ tr/0-9.//cd;
    $arg = pack('U*',split(/./,$arg));

    return $arg;
}

sub to_vstring_3 {
    my ($arg) = @_;

    $arg =~ tr/0-9.//cd;
    $arg =~ s/[._]?(d+)/chr($1 & 0x0FFFF)/eg;

    return $arg;
}

那么,还有第四种方法吗？