Our holyness divined a riddle to me, which I am unworthy to understand. Perhaps the higher clergy can guide my way. 
package Data::CryptRecord;
BEGIN {
    use strict;
    [ ... ]
    our %ENGINES;
}

sub register { ... } # adds to the %ENGINES hash

# List what's in the hash
sub list_engines {
    my $self = shift;

    my @eng;
    while( my ($k, $v) = each(%ENGINES)){
        push @eng, $v->{'name'};
    }

    return @eng;
}

# Chose a distinct crypt method for this instance
# Lot's of list_engines included for debugging
sub set_engine {
    my ($self, $name) = @_;
    
    $name = uc($name);
    print "Enter set_engine (" . scalar $self->list_engines . ")\n";
    while( my ($k, $v) = each(%ENGINES)){
        next unless(uc($v->{'name'}) eq $name);
        $self->{'enc_type'} = $k;
        print "Exit OK set_engine (" . scalar $self->list_engines . ")
+\n";
        return 0;
    }
    print "Exit fail set_engine (" . scalar $self->list_engines . ")\n
+";
    return -1;
}

[download]
And this is what happens, when the program calls set_engine 
(not shown, at the end of the CTOR)
Blessed List(1)
Enter set_engine(1)
Exit OK set_engine (0)
after set_list (1)
(This is another list_engines called later in the program)

[download]

So sometimes %ENGINES appears to be empty, but it recovers magically. Does anyone have an idea, where to start the search?

BTW: The program has a ncurses UI, therefore perl -d is tedious. Is there a way to redirect the debugging console to a different VT or XTerm?

Humbly praying for revelations ...
- lesage

Thanks a lot for your help. The crucial issue was resetting the each() iterator. So special thanks to ProfVince and shmem.

Still, use warnings; and clarification that BEGIN{} is in no way a special scope, were also very helpful.

I meanwhile figured out that

export PERLDB_OPTS='TTY=/dev/pts/2'
perl -d ./myprg.pl

[download]

can be used to redirect the perl debugger console. Tying e.g. a picocom on its own pty does almost what I'd like to have -- apart from local echo and CR/LF conversion. I'd bet there is a Perl program around doing such things. Does anybody have a pointer?

- lesage

In reply to Perl Riddle by lesage

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