I used to love Perl until the world told me to stop because the syntax was too noisy. Now I'm embedding JavaScript expressions in CSS in JSX in ES6 and being told this is an evolved state.
An informed rant about Perl might include these two function calls behaving differently and one almost certainly containing a bug, because function arguments are always a list:
some_function(@an_array, $a_scalar);
some_function2($a_scalar, @an_array);
Lack of function signatures is another good complaint about Perl. It's still not realistic to use them in code that ships for old Perl versions (like for deployment on leading server distributions).
There are others, but, yeah. I also hate how simplistic criticism of Perl is these days. It's knee jerk and poorly-informed in most cases. That doesn't mean I'm recommending Perl for everyone, or that I'd pick it for every new project, just that I wish the dialog around it weren't so stupid so much of the time.
sub foo(@array,$scalar) { }
foo( 42, [1,2,3] ); # compile time error
I find it kind of funny primes are constantly used as a first filter on using Perl 6, despite it being one of the only languages with an efficient built in .is-prime method on integer types >;P I have a more contemporary version of Rakudo built locally too, so can see if this is something that's already gone away if you dont mind throwing your code in a gist/pastebin somewhere?
perl6 0m6.615s https://p.thorsen.pm/ab1769fe2778
This is Rakudo version 2017.10 built on MoarVM version 2017.10 implementing Perl 6.c. It's built with radkudobrew. Results are consistent across several platforms, I've also built on an iMac with OS X 10.1. This one is built on Ubuntu 16.04 x86-64.
FWIW, if I would just be interested in the prime numbers upto 1000, I would write that like this:
(1..1000).grep( *.is-prime )
(1..2500).hyper.grep( *.is-prime )
Am currently researching as to why your Perl 6 algorithm is so slow.
sieve_sundaram(1000)
sieve_sundaram(1e3)
Also, you seem to have a sub-optimal algorithm: the second `foreach` doesn't need to go from `1..$n`, but can go from `$i..$n` instead. This brings down the runtime of the Perl 5 version of the code to 89 msecs for me.
Since your program is not using BigInt in the Perl 5 version, it is basically using native integers. In Perl 6, all integer calculations are always BigInts, unless you mark them as native. If I adjust your Perl 6 version for this, the runtime goes down from 4671 msecs to 414 msecs for this version:
sub sieve_sundaram(int $n) {
my %a;
my int @s = 2;
my int $m = $n div 2 - 1;
for 1..$n -> int $i {
for $i..$n -> int $j {
my int $p = $i + $j + 2 * $i * $j;
if $p < $m {
%a{$p} = True;
}
}
}
for 1..$m -> int $k {
if ! %a{$k} {
my int $q = 2 * $k + 1;
@s.push($q);
}
}
return @s;
}
sieve_sundaram(1000);
I could further make this idiomatic Perl 6, but the most idiomatic version I've already mentioned: `(1..1000).grep( *.is-prime)`
Or on IRC: #perl6 on irc.freenode.org ?
Or the perl6-users mailing list?
The fact that it has managed to evolve into a decent, if poorly typed language, with some outstanding implementations, while maintaining 99% compatibility with "onmouseover" scripts from the 90s is a testament to its sound design.
Do you still run anything on Node.js 0.10? 0.10.36 was released in 2015, the same year as Perl 5.20. I doubt the mojority of modules still support it.
We target 5.10.1. When CentOS 6 is EOL, we will target 5.16, and so on. I don't like it, but I can't make Red Hat ship newer Perl versions. Software Collections has Perl 5.20, which is great for some folks, but it's not a good option for our projects, either.
It's worth noting that Python has the same problem on RHEL/CentOS. Maybe even more pronounced, because some system tools rely on Python, and it can even break them if you change your personal Python to something else (I use pyenv, and I have to remember to change my Python back to the system one when running Gnome Tweak Tool, and the like).
So, I'm excited about it, too, but I can't use them until CentOS/RHEL 7 reaches end of life (and that's assuming CentOS/RHEL 8 gets a 5.20+ version of Perl, which isn't an entirely safe assumption). It's easy to blame CentOS/RHEL for this, because they ship an old-as-heck Perl version, but it's also reasonable to question why it took 20+ years for Perl to get function signatures in the core language.