Re^14: Hash order randomization is coming, are you ready?

[Anonymous Monk]

If there is any reluctance it is purely that of me wanting to avoid a long dialog repeating what has already been said elsewhere. I have a lot of demands on my time these days.

Great, link?

[demerphq]

Re^2: Hash order randomization is coming, are you ready? summaries most of the relevant material quite well.

[Anonymous Monk]

I have much respect for you and p5p, I mean no disrespect with my comments, I'm grateful for perl, but please listen to the stinkers now while its early :) sometimes they have points, even if they don't understand the topic thoroughly

:) I came up with those links (after I noticed my earlier "What?" got --), and its lacking a lot of details -- I guess I just don't get it. I'm not quite ready to call it garbage like BrowserUk , but I'm certainly thinking about it :) new smells aren't pleasant

I'm thinking this change is one of those things I think should be delayed for at least another 5 years until warnings can warn you about it, and the docs contain something more demonstrative , and aren't set to permanent limbo mode (forgive my lack of precision in my wording)

"Don't depend on this" is beginning to chafe, grate even :) why not a hash pragma so it DWIMs (whatever that would be)?

Also, when claims are made about performance in the docs, link to it, for example Switch perl's hash function to MurmurHash-32 (v3) and hash randomization by default. « perl5-porters « ActiveState List Archives

I thought we had "per process hash randomization" from 5.8.1, and nothing I linked earlier describes something new/different -- this thread makes it sound its more random than that -- yup, I don't get it, docs aren't clear

Reading that PERL_HASH_SEED now takes a hex value instead? Code parsing this output, should it exist, must change to accomodate the new format. ? Change for the sake of change?

Yup, I hate that variable now :) ${magic variables}-- I think I'm onto something with the hash pragma idea and delaying introduction -- improve the docs/interface while its new and you know what its all about

I have much respect for you and p5p, I mean no disrespect with my comments, I'm grateful for perl, but please listen to the stinkers now while its early :) sometimes they have points, even if they don't understand the topic thoroughly

[ikegami]

I thought we had "per process hash randomization" from 5.8.1, and nothing I linked earlier describes something new/different

Until 5.18, only some hashes are randomized (with a per-process seed). Starting with 5.18, all hashes will be randomized (with a per-process seed).

From a programmer's perspective, nothing has changed. It means you can't rely on the order in which the keys of a hash a returned by keys (except the documented exception). This is nothing new, yet dmq's change caused many distributions on CPAN to start failing. (The problems tended to be with the tests themselves, not the modules being tested.)