#! /usr/bin/perl
# write-read-execute code

my %hash = ();

# btw, all of a sudden there is a syntax error near: $hash{
# I have no idea why (can't test this, while simular code works?)
$hash{'code'} = sub { print "Hi Guy - Hello Fellow!\n" };
&$hash{'code'}();

my $string = toStr($hash{'code'};
$hash{'code'} = toCode( split(/\n/, $string) );

# this should work (as before saved):
&$hash{'code'}();

# the two subs
sub toStr { 
    use B::Deparse;
    return B::Deparse->new("-p", "-sC")->coderef2text( shift )."\n";
}

sub toCode {
    my $ret;
    while ( @_ )
    {
        $ret .= (shift)."\n"; # "\n" was eliminated by split
    }
    # NOW MAKE $ret been executed:
    # This is the examlpe of B:Deparse:
    eval "sub func $ret"; # but nothing happens

    # this causes this mistake:
    # Undefined subroutine &sub
    &{$ret};

    # this should be given back:
    return $ret;
}
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Sorry, FINAL solution.


Please have a look at the second: print $hash{code},"\n";
It prints a CODE(0x..)-Ref, but is not executable. Any Hints, Thanks, Carl

#! /usr/bin/perl
# Write-Read-Execute code
#

    my %hash = ();
    $hash{code} = sub { print "Hi Guy - Hello Fellow!\n" };
    &{$hash{code}}();
    print $hash{code},"\n";

    my $string = str_Code($hash{code});
    $hash{code} = code_String( split(/\n/, $string) );

    # this should work (as before saved):
    print $hash{code},"\n";
    &{$hash{code}}();

# the two subs
sub str_Code {
    use B::Deparse;
    return B::Deparse->new("-p", "-sC")->coderef2text( shift )."\n";
}

sub code_String {
    my $ret;
    while ( @_ )
    {
        $ret .= (shift)."\n"; # "\n" was eliminated by split
    }
    # NOW MAKE $ret been executed:
    # This is the examlpe of B:Deparse:
    #eval "sub func $ret"; # but nothing happens

    # this causes this mistake:
    # Undefined subroutine &sub
    #&{$ret};

    # this should be given back:
    return \&{$ret};
}
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To be honest I'm not sure what you're trying to do with code_String().

All coderef2text() does is produce a string that, on eval(), will do what the coderef does. If you want to turn that string into a coderef just wrap it in a sub..

The following should illustrate.

#! /usr/bin/perl

use strict;
use warnings;
use B::Deparse; 

sub str_code {
    my $coderef = shift;
    return "sub " . B::Deparse->new("-sC")->coderef2text( $coderef );
}

my $coderef = sub { print "Hello world\n" };

print "We have a coderef $coderef\n";

print "Which we can run like this: ";
$coderef->();

my $deparsed_coderef = str_code( $coderef );
print "Which we can deparse to this: $deparsed_coderef\n";

my $new_coderef = eval $deparsed_coderef;
print "Which we can eval to another coderef $coderef\n";

print "Which we can run just like the original: ";
$new_coderef->();

__END__
# produces
We have a coderef CODE(0x361a98)
Which we can run like this: Hello world
Which we can deparse to this: sub {
    use warnings;
    use strict 'refs';
    print "Hello world\n";
}
Which we can eval to another coderef CODE(0x361a98)
Which we can run just like the original: Hello world
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