Perl 5.22 Released

kthreadd writes: Version 5.22 of the Perl programming language has just been released. A major new feature in this release is the double diamond operator; like the regular diamond operator it allows you to quickly read through files specified on the command line but does this in a much safer way by not evaluating special characters in the file names. Other new features include hexadecimal floating point numbers, improved variable aliasing and a nicer syntax for repetition in list assignment. Also, historical Perl modules CGI.pm and Module::Build are removed from the core distribution.

Comments

Re:Second post!

[bobbied]

So was it Perl 6 or you that failed?

hexadecimal floating point numbers?

[gimballock]

What's the use case for hexadecimal floating point numbers? Seems like a "Why not" feature.

Re:hexadecimal floating point numbers?

[gameboyhippo]

And the funniest part of this all, is that exponential notation had to be changed to use p rather than e since e is a hexadecimal number.

Re:hexadecimal floating point numbers?

[suutar]

It probably is mostly a "why not". I expect there will be a very few folks who will get some use out of being able to really specify an exact floating point value, though, instead of specifying a decimal float and having it turned into "the IEEE double which is closer than any other to that value".

Re:hexadecimal floating point numbers?

[gnasher719]

What's the use case for hexadecimal floating point numbers? Seems like a "Why not" feature.

Useful when you implement high quality transcendental functions and need floating-point constants that are guaranteed to be converted exactly as intended.

Re:hexadecimal floating point numbers?

[bobbied]

What's the use case for hexadecimal floating point numbers? Seems like a "Why not" feature.

Oh no.. It's for the obfuscated Perl contest.... You can do amazing things with that..

Re:hexadecimal floating point numbers?

[serviscope_minor]

The use of hex floats is to be able to write out floats efficiently and with guaranteed full accuracy to a text file. You can use decimal but you need a LOT of digits in order to do so, making the files rather bloaty. The reason Perl now supports them I suspect is because they're now supported in a bunch of other languages such as C++, so if you want to be able to mutually exchange data, you need hex floats in perl too.

Pesonally, I like them. A lot of data one generates in numerics isn't exactly human readable, but is generated as text for easy parsing with the original language and other tools. For example if your algorithm generates a log of checkpoints you can restart interrupted computations (great for splitting work into smaller chunks for a cluster), for example. To do that properly, you need to be able to save the state without loss.

That's just one of many examples.

It's curious that people (not you) have been guffawing over how stupid Perl is for doing this. It's funny that a supposedly hackish community has a significant cadre who brags about their anti-intellectualism as much as any self-respecting highschooler.

Re:Perl still around?

[Anonymous Coward]

I work as a system administrator and although Python is quite popular nowadays I would say Perl is still one of the go-to choices for a lot of sysadmins. Sure Python is doing just fine, a lot of people use it; but I wouldn't say that it has replaced Perl in any way.

Re:News that matters!

[plopez]

Oblig:

BEFOREHAND: close door, each window & exit; wait until time;
        open spell book; study; read (spell, $scan, select); tell us;
write it, print the hex while each watches,
        reverse length, write again;
                      kill spiders, pop them, chop, split, kill them.
                            unlink arms, shift, wait and listen (listening, wait).
sort the flock (then, warn "the goats", kill "the sheep");
        kill them, dump qualms, shift moralities,
                      values aside, each one;
                              die sheep; die (to, reverse the => system
                                            you accept (reject, respect));
next step,
        kill next sacrifice, each sacrifice,
                      wait, redo ritual until "all the spirits are pleased";
        do it ("as they say").
do it(*everyone***must***participate***in***forbidden**s*e*x*).
return last victim; package body;
        exit crypt (time, times & "half a time") & close it.
                      select (quickly) and warn next victim;
AFTERWARDS: tell nobody.
        wait, wait until time;
                      wait until next year, next decade;
                              sleep, sleep, die yourself,
                                            die @last

Re:Perl still around?

[prof_robinson]

Perl isn't going anywhere. In fact, installs and contributions to CPAN are up almost 1200% in the last 10 years. What's happened to Perl, is it's become ubiquitous...it's literally everywhere. It's not our fault you haven't noticed.

Re:Perl still around?

[rduke15]

Replaced where? Apparently not on my Debian servers:

# find /etc /bin /sbin /usr/bin /usr/sbin -type f | xargs file | grep "Perl script" | wc -l
119
# find /etc /bin /sbin /usr/bin /usr/sbin -type f | xargs file | grep "Python script" | wc -l
29

Re:News that matters!

[plopez]

I forgot the header
# Black Perl, adapted for Perl 5 by Jonadab.
# Adapted from Black Perl, as seen in the Camel,
# 2nd ed., p 553

use the 4's

[Anonymous Coward]

$ perl -e 'print 0xC3P0'
195
$

Re:Impossible to care anymore

[bill_mcgonigle]

Perl updates for the past ten years have been mostly unloved features and cruft. If 5.6 didn't get the job done then 5.22 won't either.

This is just a "look at me, I'm uninformed about the languages landscape" post (good thing you went AC). Like Perl or not, most people who care about open source development know that the Perl nuts have been busy backporting the ideas that were supposed to show up in Perl 6 to Perl 5.

Whether or not that goes anywhere is separate from being ignorant about what's going on.

Re:Perl still around?

[plopez]

In those days they used punch cards so there *was* justification, it was a limitation of technology available at the time. To reintroduce it, 4 years after it was abandoned by Fortran 90, is a serious lapse of good sense. There is no good reason to have it other than as a joke or out of sadism.

Re:Perl still around?

[plopez]

"Etc.. You try a few..."

Graph databases = network databases and they sucked then as now
NoSQL databases = recipe card and network DBs and they sucked then and suck now
Java VM = UCSD Pascal
VMs = IBM VM OS
DevOps = 80's and 90's start ups where you had to do everything.... and it sucked
Browser = Thin client
IM = IRC
XQuery = Heirarchical databases which sucked then and suck now
OO languiages such as Java are converging on LISP and the LISP family of programming languages vindicating a language approach invented in the 50's and which does not suck.

That's what immediately comes to mind.

Re:Perl still around?

[__aaclcg7560]

On my FreeNAS file server:

# find /etc /bin /sbin /usr/bin /usr/sbin -type f | xargs file | grep "Perl script" | wc -l
2
# find /etc /bin /sbin /usr/bin /usr/sbin -type f | xargs file | grep "Python script" | wc -l
2

Maybe not a fair comparison. :)