in reply to Re^2: pack() returns an unusable string
in thread pack() returns an unusable string

And here's a version with Data::Dumper and some config vars that also works. 

#!/usr/bin/perl -l

use strict; # https://perlmonks.org/?node_id=11133064
use warnings;

my $template = 'd<';
my $nv = 2.4;
$nv = 4135;                     # NOTE errors for this number
my $p = pack $template, $nv;
use Data::Dumper;
$Data::Dumper::Terse = $Data::Dumper::Useqq = 1;
my $s = Dumper $p;
print ">$s<\n";

system $^X, '-wle', "use strict; print unpack('H*', $s);";

[download]

Outputs: 

>"\0\0\0\0\0'\260\@"
<

000000000027b040

[download]

note that it adds a newline, but perl doesn't care.

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Re^4: pack() returns an unusable string
by syphilis (Archbishop) on May 27, 2021 at 02:39 UTC
    And here's a version with Data::Dumper and some config vars that also works

    Neither this nor the rendition using Data::Dump works for me on Windows: 
    C:\_32\pscrpt>type test3.pl

use strict; # https://perlmonks.org/?node_id=11133064
use warnings;

my $template = 'd<';
my $nv = 2.4;
$nv = 4135;                     # NOTE errors for this number
my $p = pack $template, $nv;
use Data::Dumper;
$Data::Dumper::Terse = $Data::Dumper::Useqq = 1;
my $s = Dumper $p;
print ">$s<\n";

system $^X, '-wle', "use strict; print unpack('H*', $s);";

C:\_32\pscrpt>perl test3.pl
>"\0\0\0\0\0'\260\@"
<
syntax error at -e line 1, at EOF
Execution of -e aborted due to compilation errors.

C:\_32\pscrpt>

    [download]
    I guess it's something to do with Windows command line quoting rules.
    Mind you, having it work on Windows specifically is not important.
    Now that I have a working example, I can while away some time porting your fix to Windows when I have nothing better to do.

    Thanks tybalt89 !!

    Cheers,
    Rob

    Thanks
[reply]
[d/l]

      Just another guess (to tweak GrandFather) because I don't have a Windows system to test on. 

      #!/usr/bin/perl -l

use strict; # https://perlmonks.org/?node_id=11133064
use warnings;

my $template = 'd<';
my $nv = 2.4;
$nv = 4135;                     # NOTE errors for this number
my $p = pack $template, $nv;
use Data::Dump qw(pp);
my $s = (pp $p) =~ s/"(.*)"/qq($1)/sr; # tweak for different delimiter
print ">$s<\n";

system $^X, '-wle', "use strict; print unpack('H*', $s);";

      [download]
[reply]
[d/l]
        Just another guess ...

        Yes, that works fine on Windows as is: 
        C:\_32\pscrpt>perl test4.pl
>qq(\0\0\0\0\0'\xB0\@)<
000000000027b040

        [download]
        But not when I change $template to "D<" and $nv to 2.4: 
        C:\_32\pscrpt>perl test4.pl
>pack(qq(H*","9a999999999999990040000000000000))<
syntax error at -e line 1, at EOF
Execution of -e aborted due to compilation errors.

        [download]
        (I can dig into this later if you're getting tired of it.)

        Cheers,
        Rob
[reply]
[d/l]
[select]

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