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The three of us met today, and we:

• updated the status of stalled PPCs (after discussion with the proposers)
• assigned a number (0023) to the map my $x { } PPC
• discussed the evaluation order issue related to PPC 0021 (optional chaining)
• decided that future rejected PPCs should have a section that details why they were rejected
• discussed the tooling around the publication of dual-life modules on CPAN

Well end of day two here and had a nice walk and a nice chat with one of the local city counselors who was out glad handing I asked her when the Gardiner Express Way will be fixed up. She said by Christmas ;)

That was a Local joke now onto what I got up to today.

Ovid despite Air Frances best efforts actually did make in to the conference late the night before so he was able to give his Keynote on OO in the Perl Core, Seems we will be getting something called Corinna Soon we will have Field, Class, Role and Method to play with and if you are brave you can get the latest version of perl and play with a few parts of it. The key sticky part is Typing, Seems there is another project out there called Oshum to handle all those nasty typing problems. Well to quote the main character Sweden's best know literature

'We shall see, what we shall see'

These are some answers to the Week 263, Task 2, of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Spoiler Alert: This weekly challenge deadline is due in a few days from now (on April 7, 2024 at 23:59). This blog post provides some solutions to this challenge. Please don’t read on if you intend to complete the challenge on your own.

Task 2: Merge Items

You are given two 2-D array of positive integers, $items1 and $items2 where element is pair of (item_id, item_quantity).

Write a script to return the merged items.

Example 1

SQL::Inserter is new CPAN module based on what we are using at SpareRoom to easily manage buffered inserts, as well as to replace SQL::Abstract's slow insert method.

Inserter OO interface

The idea is that if you want to insert many rows of data (e.g. part of an ETL pipeline, or writing logs etc), you'd want to be doing that with multi-row INSERT statements. With SQL::Inserter you create a very lightweight object to handle inserting for you, just pass it a DBI db handle, the table name and the columns you'll be inserting (optional if you use hashes for inserting, see next section):

This week, for its first meeting, the new PSC:

• discussed the nature of typing systems for Perl and what properties we find desirable vs not
• worked out a release schedule for the next few months of devel releases
• reviewed the PPC Tracker document. A few are now done, the rest need remainder nudge emails to their respective proposers

Hello everybody! It's another week with a new Perl Weekly Challenge. This week I'm only doing the first challenge, not because of time, but because the second challenge makes absolutely no sense to me. Perhaps a clarification will come out, but I'm not going to bother at the moment.

This week the challenge is to find the number of primes under the provided number. This is a challenge that really isn't worth rebuilding, and so I would recommend using Math::Prime::Util. You have to know when to just trust the professionals and use modules. With the use of M::P::U, we can essentially do the challenge in one line.

use Math::Prime::Util 'primes';
say scalar @{primes(shift)};

primes() returns an array reference, so we have to dereference the array after calling the function. We shift the number that is entered, call primes (which provides an array of the primes under that number), and dereference it and count it to print the answer.

It's that simple! This is a case where I definitely wouldn't recommend writing your own custom prime finder. I'll hopefully see you next week with the next challenge!

These are some answers to the Week 223, task 1, of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Spoiler Alert: This weekly challenge deadline is due in a few days from now (on July 2, 2023 at 23:59). This blog post offers some solutions to this challenge. Please don’t read on if you intend to complete the challenge on your own.

Task 1: Count Primes

You are given a positive integer, $n.

Write a script to find the total count of primes less than or equal to the given integer.

Example 1

Input: $n = 10
Output: 4

Since there are 4 primes (2,3,5,7) less than or equal to 10.

Example 2

Input: $n = 1
Output: 0

Example 3

In my recent Cloud Comparison, I mentioned that I'd look at Spot VM pricing in an update. This is the update - 6 out of the 10 providers tested offer Spot/Preemptible instance pricing.

At SpareRoom we make some good use of Spot VMs. E.g. our perl test suite gets to run on fast VM types at very low cost: currently we are using c3-highcpu-22 instances which normally come at $0.95/hour each. The spot pricing for them is more than 10x lower, at just $0.086/h. At these prices, if our test suite needed it (it's already fast), we'd be able to launch c3-highcpu-176 (176 vCPUs) at well under $1/h!

Today was PSC 111 — what happened to 110 you ask? Well, it was a bit of a non-meeting a few weeks ago. Nothing to say about it, sorry!

This week, we:

• Said hello to Graham and goodbye to Rik
• We did a bunch of handover, making sure we set up a new Zoom meeting and calendar, and talking about our usual order of business

In more normal business, we:

• talked about the future of use vX, especially related to builtin:: stuff — do we want “use v5.40” to import “builtin::refaddr” for example
• talked about what we’re going to do with the UNIVERSAL::import changes so we can move it forward toward someday making it fatal but without breaking half of CPAN at once

Finally have a chance to go to a North American Perl event, so after nearly 4 years since my last Perl event, thanks Covid 19 I managed to make my way down from the Ivory Tower in Ottawa to the 'Big Smoke', 'Hogtown', Queen City, TO or as most of the rest of the world knows it Toronto.

So there are about 100 us us Perl types here today, with most participants coming from across the US and Canada but there are a few that came over 'The Big Pond'

So far The talks have been very good, I had a and interesting Talk on Test2 by Chad Granum something I will have to look into as my old test suite is becoming a little flimsy and is a patchwork of kludges,

These are some answers to the Week 263, Task 1, of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Spoiler Alert: This weekly challenge deadline is due in a few days from now (on April 7, 2024 at 23:59). This blog post provides some solutions to this challenge. Please don’t read on if you intend to complete the challenge on your own.

Task 1: Target Index

You are given an array of integers, @ints and a target element $k.

Write a script to return the list of indices in the sorted array where the element is same as the given target element.

Example 1

Input: @ints = (1, 5, 3, 2, 4, 2), $k = 2
Output: (1, 2)

Sorted array: (1, 2, 2, 3, 4, 5)
Target indices: (1, 2) as $ints[1] = 2 and $k[2] = 2

Example 2

To celebrate the upcoming release of Perl 5.38 we are excited to offer Limited Edition* merchandise.

The design was a true team effort by the marketing committee and is inspired by the traditional Perl camel logo. We had a lot of fun throwing around ideas, then throwing them in to AI to see what it's randomness would come back with. We then passed the ideas to our artist for the final result.

Check them out on the official Perl store where proceeds go to The Perl and Raku Foundation which then directly fund grants etc.

* TBD how limited.

Hi everybody! Just doing the first weekly challenge task again this week. This week we're sorting a list of numbers and then checking whether the number matches the same position in the unsorted list. It's a very simple challenge and easily written in about 4 actual lines of clean code.

Here's the code:

#!/usr/bin/perl
use strict;
use v5.24;
my @sorted = sort @ARGV;
my $matches;
for (my $i = 0; $i <= $#ARGV; $i++) {$matches++ if $ARGV[$i] == $sorted[$i]}
say $matches // 0;

At SpareRoom we still use Apache/mod_perl and, despite Devel::NYTProf::Apache's warnings about it not being maintained, it is still the best way for profiling Perl.

All you need to do really, for a mod_perl app, is to include this in your Apache config:

PerlPassEnv NYTPROF # Not needed for default settings.
PerlModule Devel::NYTProf::Apache

You should also allow a single worker/child, and make sure it terminates cleanly before processing the output (nytprofhtml).

Since I want my dev/test environments to normally run with multiple workers and no profiler attached, I have a bash alias that exits apache and restarts it set-up for profiling. I thought I'd share an example of that, as I find it very useful.

First, a basic example pulled from what I used on our older CentOS/RedHat VM:

These are some answers to the Week 262, Task 2, of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Spoiler Alert: This weekly challenge deadline is due in a few days from now (on March 31, 2024 at 23:59). This blog post provides some solutions to this challenge. Please don’t read on if you intend to complete the challenge on your own.

Task 2: Count Equal Divisible

You are given an array of integers, @ints and an integer $k.

Write a script to return the number of pairs (i, j) where

a) 0 <= i < j < size of @ints

b) ints[i] == ints[j]

c) i x j is divisible by k

Example 1

Graydon Hoare:

[…] Corporate-employed FOSS maintainers working at a firm with these [very common] “growth and novelty” incentives [… are] in a position where their job performance is very likely to be evaluated in terms of visible growth and novelty (it might be dressed up in more abstract terms like “real-world impact” or “visibility” but it still means the same thing) even though that is exactly the wrong thing for the health of the project they’re maintaining.

I’m excerpting the gist of his article here but actually I suggest reading all of it. It’s not very long but gives flesh to this skeleton argument.

It doesn’t help that what he is talking about isn’t limited to employed maintainers; profit is not the only growth incentive structure that can lead to this novelty mindset, so this can exist entirely outside commercial context.

In which we move beyond Perfect Permutation.

Hi everybody, just a quick one this week. Again it's been a very busy week, so I wrote this one quick to print the sorted list of all common characters in all the words provided. That's the simple explanation of this week's challenge.

Here's the code:

my @results;
my $first_word = shift;
for my $letter (split(//, $first_word)) {
    push(@results, lc($letter)) if (grep {$_ =~ /$letter/i} @ARGV) == @ARGV;
}
@results = sort @results;
say $_ foreach @results;

These are some answers to the Week 262, Task 1, of the Perl Weekly Challenge organized by Mohammad S. Anwar.

Spoiler Alert: This weekly challenge deadline is due in a few days from now (on March 31, 2024 at 23:59). This blog post provides some solutions to this challenge. Please don’t read on if you intend to complete the challenge on your own.

Task 1: Max Positive Negative

You are given an array of integers, @ints.

Write a script to return the maximum number of either positive or negative integers in the given array.

Example 1

Input: @ints = (-3, 1, 2, -1, 3, -2, 4)
Output: 4

Count of positive integers: 4
Count of negative integers: 3
Maximum of count of positive and negative integers: 4

Example 2

Today’s PSC call was another pretty short one.

• We agreed on the change HTTP::Tiny, our last blocker, and hope to have RC1 tomorrow.
• There are a few minor notes on the RC0 status on p5p, which need addressing. Nothing major.
• We discussed the things we need to do to arrange the next PSC election, scheduled for post-v5.38.0.
• We discussed libperl.t, which fails on newest macOS+Xcode even in stable. It’s fixed in blead, and we should fix maint-5.36, too