Re^2: (FIRST|NEXT)KEY in context

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.

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Re^3: (FIRST\|NEXT)KEY in context by johnvk (Initiate) on Feb 12, 2010 at 13:25 UTC
i'm not sure if you were answering my question or trying to ask a question yourself. In your case, the reason why you get an infinite loop is that the `keys()` call resets the iterator that is shared among `each()`, `keys()` and `values()`;. so in your loop the iterator gets set to the beginning every iteration by the call to `keys()` but the docs you pointed to explain that. so i presume you knew that. if this is supposed to be an answer to my query, i aplogize but i dont understand. in particular, my issue only comes up when the hash is *tied*. As for moving my query to its own thread, i actually wantd it here, because it appears the OP and i are asking the same question. I figured i'd keep perlmonks organized by keeping the topic all in one place. Are you saying i'll get less attn as a reply rather than an original post? Thanks.	[reply] [d/l] [select]
Re^4: (FIRST\|NEXT)KEY in context by Anonymous Monk on Feb 13, 2010 at 01:45 UTC
in particular, my issue only comes up when the hash is tied. Because you call keys immediately before calling each.	[reply]