hi hurricup,

Excerpts from the man pages:

each "When called on a hash in list context, returns a 2-element list consisting of the key and value for the next element of a hash."

keys "Called in list context, returns a list consisting of all the keys of the named hash."

values "In list context, returns a list consisting of all the values of the named hash."

As you can see the example below each is executed repeatedly however keys and values are called only once. 

use strict;
use warnings;

my %hash = ('Hello' => 'World');
while ( my ( $key, $value ) = each %hash ) {
      #my %otherhash = %hash;
      print "\n$key=$value";
}

print "\n------------------\n";

foreach ( keys %hash ) {
      my %otherhash = %hash;
      print "\n$_=$hash{$_}";
}

print "\n------------------\n";

foreach ( each %hash ) {
      my %otherhash = %hash;
      print "\n$_\n";
}

print "\n------------------\n";

[download]

In reply to Re: Peek a hash without breaking iterator by pme
in thread Peek a hash without breaking iterator by hurricup

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.