this is output with Dumper.

$VAR1 = 'main';
$VAR2 = 'D:\\test.pl';
$VAR3 = 12;
$VAR4 = 'main::__ANON__';
$VAR5 = 1;
$VAR6 = undef;
$VAR7 = undef;
$VAR8 = undef;
$VAR9 = 0;
$VAR10 = '





';
$VAR1 = 'main';
$VAR2 = 'D:\\test.pl';
$VAR3 = 13;
$VAR4 = 'main::__ANON__';
$VAR5 = 1;
$VAR6 = undef;
$VAR7 = undef;
$VAR8 = undef;
$VAR9 = 0;
$VAR10 = '





';
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it seem not useful.caller only return these values

    #  0         1          2      3            4
    ($package, $filename, $line, $subroutine, $hasargs,
    #  5          6          7            8       9         10
    $wantarray, $evaltext, $is_require, $hints, $bitmask, $hinthash)  
+= caller($i);
[download]

maybe we should try another way.