I don't understand. Why would $guid{218827} be auto-vivified? Note that $guid{218827} is referenced from a subroutine, which isn't executed until after the BEGIN block.

I think there's a bug in Perl. Watch what happens if you dump the content of %guid in the BEGIN block: 

#!/usr/bin/perl
     
use warnings;
         
            
my %guid=(218827=>5,109940=>2);
          
BEGIN 
{
    %handle=
    (
        cmd => sub
        {
            my $ref = sub{$guid{218827}++;warn "sub: $guid{218827}";};
            $ref->();
        },
    );
    while (my ($key, $value) = each %guid) {
        print defined $key ? $key : "UNDEF";
        print ":";
        print defined $value ? $value : "UNDEF";
        print "\n";
    }
}        
            

$handle{cmd}->();
__END__
sub: 6 at buu line 14.

[download]
Not only does it show that the BEGIN block doesn't autovivify the value, the error disappears as well!

In fact, just about any reference to %guid (like keys %guid;, %guid;, or $guid {1};) after the assignment to %handle makes the error go away.

This ought to be perlbugged.

Abigail

In reply to Re: modification of read-only in hash ++ by Abigail-II
in thread modification of read-only in hash ++ by BUU

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