Beefy Boxes and Bandwidth Generously Provided by pair Networks
Syntactic Confectionery Delight

comment on

( #3333=superdoc: print w/replies, xml ) Need Help??

So, if I understand correctly, the code you posted is visibly broken and has been for a very long time.

Well yes, it is broken, that was my point for bringing it up :-). Whether it is visibly broken or not depends on whether you have any collisions. In the case you posted there are two sets of collisions, 4 and 1, and 3 and 0. (You can tell because they reverse each copy in earlier perls.) However if changed it to be 1,2,3,5,7,8 you would not have any collisions and the order would appear the same. Eg try:

my %hash = map { $_ => 1 } (1,2,3,5,7,8);

In 5.18 the order will be different for every hash. No exceptions. Here is what perlfunc will say in 5.18:

Hash entries are returned in an apparently random order. The actual r +andom order is specific to a given hash; the exact same series of operations on two hashes may result in a different order for each hash. Any inser +tion into the hash may change the order, as will any deletion, with the exc +eption that the most recent key returned by C<each> or C<keys> may be deleted without changing the order. So long as a given hash is unmodified you +may rely on C<keys>, C<values> and C<each> to repeatedly return the same o +rder as each other. See L<perlsec/"Algorithmic Complexity Attacks"> for details on why hash order is randomized. Aside from the guarantees provided here the exact details of Perl's hash algorithm and the hash traversal order are subject to change in any release of Perl.

In reply to Re^4: Hash order randomization is coming, are you ready? by demerphq
in thread Hash order randomization is coming, are you ready? by demerphq

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

  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or or How to display code and escape characters are good places to start.
Log In?

What's my password?
Create A New User
Domain Nodelet?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others pondering the Monastery: (5)
As of 2022-05-23 08:11 GMT
Find Nodes?
    Voting Booth?
    Do you prefer to work remotely?

    Results (81 votes). Check out past polls.