Observe an infinite loop 
my %foo = 1 .. 10;
while(my($k,$v) = each %foo){
    print "k($k)v($v)\n";
}

while(my($k,$v) = each %foo){
    print "k($k)v($v)", scalar keys %foo, "\n";
}
__END__
k(1)v(2)
k(3)v(4)
k(7)v(8)
k(9)v(10)
k(5)v(6)
k(1)v(2)5
k(1)v(2)5
k(1)v(2)5
k(1)v(2)5
k(1)v(2)5
k(1)v(2)5
...

[download]
See http://search.cpan.org/~dapm/perl-5.10.1/pod/perlfunc.pod#each, http://search.cpan.org/~dapm/perl-5.10.1/pod/perlfunc.pod#keys, http://search.cpan.org/~dapm/perl-5.10.1/pod/perlfunc.pod#values

this thread is 6 years old; nevertheless, i can't make each() work on a tied hash :(

If you /msg janitors can you please SOPWify [id://822822], they will turn your reply into a thread of its own.

In reply to Re^2: (FIRST|NEXT)KEY in context by Anonymous Monk
in thread (FIRST|NEXT)KEY in context by jweed

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