Each week Mohammad S. Anwar sends out The Weekly Challenge, a chance for all of us to come up with solutions to two weekly tasks. My
solutions are written in Python first, and then converted to Perl. It's a great way for us all to practice some coding.
You are given an array of positive integers, @ints
.
Write a script to find out if it is possible to select two or more elements of the given array such that the bitwise OR of the selected elements has at least one trailing zero in its binary representation.
So we know that a number that has at least one trialing zero is an even number (i.e. the 1 bit is not set). We also know that OR-ing a value won't remove any set bits. Therefore solving this task is as straight forward as making sure we have at least two even numbers in ints
.
def bitwise_or(ints: list) -> bool:
even_count = sum(1 for i in ints if i % 2 == 0)
return even_count >= 2
$ ./ch-1.py 1 2 3 4 5
True
$ ./ch-1.py 2 3 8 16
True
$ ./ch-1.py 1 2 5 7 9
False
You are given an array of distinct integers, @ints
.
Write a script to distribute the elements as described below:
@arr1
.@arr2
.Once you have one element in each arrays, @arr1
and @arr2
, then follow the rule below:
If the last element of the array @arr1
is greater than the last element of the array @arr2
then add the first element of the given array to @arr1
otherwise to the array @arr2
.
When done distribution, return the concatenated arrays. @arr1
and @arr2
.
For this task, I simply follow the instructions as set out in the task. With each step I remove the item from ints
, and continue until it is exhausted.
def distribute_elements(ints: list) -> list:
arr1 = [ints.pop(0)]
arr2 = [ints.pop(0)]
while ints:
if arr1[-1] > arr2[-1]:
arr1.append(ints.pop(0))
else:
arr2.append(ints.pop(0))
return arr1 + arr2
$ ./ch-2.py 2 1 3 4 5
(2, 3, 4, 5, 1)
$ ./ch-2.py 3 2 4
(3, 4, 2)
$ ./ch-2.py 5 4 3 8
(5, 3, 4, 8)
Published by /u/niceperl on Sunday 19 May 2024 07:06
Published by Unknown on Sunday 19 May 2024 09:06
Published by russbrewer on Saturday 18 May 2024 19:44
Following up on my previous post (MariaDB 10 and Perl DBIx::Class::Schema::Loader), I wanted to try the 'deploy' feature to create database tables from Schema/Result classes.
I was surprised that I could not create a table in the database when a timestamp field had a default of current_time(). The problem was that the generated CREATE TABLE entry placed quotes around 'current_timestamp()' causing an error and rejected entry.
As mentioned in a previous post, I had created file SQL/Translator/Parser/MariDB.pm as part of the effort to get MariaDB 10 clients to work correctly with DBIx::Class::Schema::Loader. Initially it was a clone of the MySQL.pm file with name substitutions. To correct the current_timestamp problem I added a search/replace in the existing create_field subroutine in the MariaDB.pm file to remove the quotes.
# current_timestamp ?
# current_timestamp (possibly as a default entry for a
# new record field), must not be quoted in the CREATE TABLE command
# provided to the database. Convert 'current_timestamp()'
# to current_timestamp() (no quotes) to prevent CREATE TABLE failure
if ( $field_def =~ /'current_timestamp\(\)'/ ) {
$field_def =~ s/'current_timestamp\(\)'/current_timestamp\(\)/;
}
This entry is made just before the subroutine returns $field_def. Now $schema->deploy(); works correctly to create the entire database.
The code shown below was tested satisfactorily to generate CREATE TABLE output (on a per table or multi-table basis) suitable for exporting (using tables Task and User as example table names):
My $schema = db_connect();
my $trans = SQL::Translator->new (
parser => 'SQL::Translator::Parser::DBIx::Class',
quote_identifiers => 1,
parser_args => {
dbic_schema => $schema,
add_fk_index => 1,
sources => [qw/
Task User
/],
},
producer => 'MariaDB',
) or die SQL::Translator->error;my $out = $trans->translate() or die $trans->error;
I believe the SQL/Translator/Parser/MySQL.pm file would benefit from this same code addition but I have not tested using a MySQL database and DBD::mysql.
Published by russbrewer on Saturday 18 May 2024 18:15
I recently set up a virtual Server Running Rocky Linux 9 as a client from which to query a remote MariaDB database. I used perlbrew to install Perl 5.38.2. I installed client related RPMs for MariaDB 10.5, I installed DBIx::Class as a relational mapper that can create Perl Schema Result Classes for each table in the database. If you are new to DBIx::Class, you can review its purpose and features in DBIx::Class::Manual::Intro. The Result Classes used by Perl to query the database are stored on the client server in a schema directory. They are created with the DBIx::Class::Schema::Loader module.
I only work with databases as a home hobbyist, but I have successfully used DBIx::Class and related DBIx::Class::Schema::Loader from a CentOS 7 server running Perl 5.24.1 with MariaDB 5.5 client related RPMs. My intent was to replace a CentOS 7 virtual server with a Rocky 9 virtual server and upgrade from MariaDB 5 client to a MariaDB 10 client.
The CentOS 7 client used DBD::mysql which works fine with MariaDB 5 but would not install on the Rocky server which used MariaDB 10 RPMs. So I installed DBD::MariaDB and DBIx::Class::Storage::DBI::MariaDB on the client Rocky server.
To create my relationship classes, I ran the schema loader and was surprised that DBIx::Class::Schema::Loader did not produce correct Result Classes on the Rocky 9 server. Later I found that it did not work properly a on Rocky 8 server either. The common issue was MariaDB version 10 compatibility with DBIx::Class::Schema::Loader (and its dependencies).
I am not sure of everything that was wrong with the Result Classes, but the obvious problems were missing the primary keys entries, missing auto_increment entries and missing unsigned integer entries for all Result Classes which should have them.
I found the problem described (but not resolved) in November 2023 in this short Perl Monks thread.
Below I describe the steps I took to get DBIx::Class::Schema::Loader and its dependencies to produce Result Classes on the MariaDB 10 client (Rocky 8 and 9) servers that was identical to that being produced on the MariaDB 5 client CentOS 7 server, remembering that all of them where creating the Result Classes by connecting to the same remote database server. Although not significant for this issue, the remote database was running smoothly on a Rocky 8 server using MariaDB 10.3.
First I noticed that the DBIx/Class/Schema/Loader/DBI directory had a mysql.pm file but had no MariaDB.pm counterpart. So I made a copy of mysql.pm named MariaDB.pm and then I edited the new MariaDB.pm file to change references to mysql and MySQL to MariaDB. Note that almost all the edits can use MariaDB as the substitute for mysql and MySQL but entries in the "_extra_column_info
" subroutine must use lowercase "mariadb
". This is because they refer to lowercase terminology expected by DBD::MariaDB as can be seen in site_perl/5.38.2/x86_64-linux/DBD/MariaDB.pm.
In DBIx/Class/Schema/Loader/DBI/MariaDB.pm, for subroutine "_extra_column_info
", keep references to mariadb in lowercase. For example:
mysql_is_auto_increment
should become mariadb_is_auto_increment
$dbi_info->{mysql_type_name}
should become $dbi_info->{mariadb_type_name}
In all other cases I used MariaDB (not mariadb) as the substitution.
I then realized that DBIx::Class::Schema::Loader depends on DBIx::Class::SQLMaker which supports a number of dependent modules such as MySQL.pm, MSSQL.pm, SQLite.pm and Oracle.pm, but did not have a corresponding MariaDB.pm file. So I made a copy of MySQL.pm named MariaDB.pm and then I edited the new MariaDB.pm file to change references to mysql and MySQL to MariaDB.
After the edits, the Schema loader started working correctly in that running Schema Loader created Schema Result Classes that matched the output of the older MariaDB 5 client.
Although apparently not directly related to the functioning of DBIx::Class::Schema:Loader, there are several other files that might need similar editing to provide full MariaDB functionality via DBIx::Class. Your Perl version may differ, but for me these modules are:
The directories contain references to other database types but do not provide a MariaDB.pm file. Inside each of the above directories, I copied the mysql.pm file and named it MariaDB.pm. Then I edited each new MariaDB.pm file to change mysql and MySQL entries to MariaDB entries. These additional MariaDB.pm files are not required to get the loader to simply create the Schema Result Classes from a database. I need to test to see what effect adding the MariaDB.pm files to these directories has on DBIx::Class functionality.
The following four files make internal references to mysql or MySQL but did not have a reference to MariaDB. Therefore, I edited each file:
For file DBIx/Class/Storage/DBI/MariaDB.pm, which is provided from CPAN, in subdirectory sqlt_type, edit to return 'MariaDB'
instead of returning 'MySQL'
.
Also change this line:
__PACKAGE__->sql_maker_class('DBIx::Class::SQLMaker::MySQL');
to this line:
__PACKAGE__->sql_maker_class('DBIx::Class::SQLMaker::MariaDB');
In the Utils.pm file there is a subroutine named ‘parse_mysql_version
’. Copy this subroutine, and name it ‘parse_MariaDB_version’. Then edit subroutine parse_MariaDB_version
to change references to MariaDB instead of MySQL. Finally, edit the Export_OK entry to include parse_MariaDB_version
.
Add a MariaDB entry to the %CDBI_auto_pkgs hash
Add a MariaDB entry to the %type_to_dbd hash
After making the essential edits I was able to produce Schema Result Classes that appear to be accurate and not missing information. After making the additional edits the Schema Loader still worked correctly.
I have not been able to do production level testing on these changes. I suspect the additional edits and some as yet unidentified edits are needed for full DBIx::Class functionality with MariaDB 10. For example, version control for using the Schema to modify the database (instead of reading the database to create the schema) is probably not working.
I have only tested the schema result class build with a command such as:
use DBIx::Class::Schema::Loader qw/ make_schema_at /;
make_schema_at(
'MyApp::Schema',
{
debug => 1,
dump_directory => './lib/test',
create => 'static',
components => [ 'TimeStamp' ]
},
[
'dbi:MariaDB:database=database_name;host=192.168.xxx.xxx', 'username',
'secret_pw', { AutoCommit => '1' }
],
);
My criterion for success was that (after just the essential edits) the MariaDB 10 clients (on my Rocky 8 and 9 servers) produced identical schema result classes as my MariaDB 5 client running on my CentOS 7 server when querying the same Maria 10 database.
My target database consists of 46 tables containing an assortment on foreign keys defining has_many, belongs_to and many_to_many relationships. The tables contain unsigned integers, unique keys, combined primary keys, auto_increment, integers (signed and unsigned), timestamp, NULLS and not_NULLS, char, varchar, and text data types.
This information is part of a work in progress and my testing is not yet complete. Use these changes at your own risk. They are offered without warranty. You should test thoroughly before incorporating them in important work. Generate your test schemas to a separate directory to avoid harming a known good schema.
If you can provide additional information, corrections and improvements, please share them.
Published by khwilliamson on Saturday 18 May 2024 17:21
t/harness: Fix grammar in comment
Published by iabyn on Saturday 18 May 2024 10:07
perldelta: add PERL_RC_STACK This is a final summary of the state of the new ref-counted stack facility at the 5.40.0 release: and is intended to be added to the 5.40.0 perldelta, to replace (rather than than be in addition to) any earlier mentions of PERL_RC_STACK in the 5.39.2 and .6 perldeltas.
Published by Perl Steering Council on Saturday 18 May 2024 09:28
This meeting was done in person at the Perl Toolchain Summit 2024.
Published by Chad 'Exodist' Granum on Saturday 18 May 2024 09:22
I just got back from the Perl Toolchain Summit 2024 in Lisbon Portugal!
Thank you to Grant Street Group for sponsoring my attendance at the event! Grant Street Group is an amazing place to work, and GSG is hiring! Contact me on irc.perl.org (Exodist) if you would like a referral.
This year I took a little side trip before the PTS to explore Lisbon with my wife. It is an amazing city, with a lot of history. I highly recommend visiting it and exploring the castles, palaces, and archaeological sights!
My goal for the PTS was to polish up Yath 2.0 and get it out the door. Spoiler alert: I did not achieve this goal, though I did make good progress. Instead several other things occurred that were even better as far as achieving things that require collaboration go!
Test2/Test2::Suite updates
I had several bug reports that built up over the last couple months. Most of my first day at the PTS was spent fixing these and minting new releases. See the changelog for Test-Simple for details. Without this event it would have been harder to find time to work all these. I also fixed a couple other modules, see my module upload list for all the modules I updated at the PTS.
PAUSE contribution
The PAUSE developers needed a way to manage concurrency. Charsbar (Kenichi Ishigaki) approached me about Parallel::Runner, which was exactly what they needed, but used some outdated modules as I have not touched it in almost a decade. I was able to mint a new release with better and more modern dependencies. Now Parallel::Runner is used under the hood for some PAUSE processes.
Using Yath to test modules on install
Additionally Garu approached me and Leon T. about using Yath as a better and universal way to test modules and upload results to cpanm. This resulted in a collaboration between myself and Leon where we made it will be possible to tell cpan, cpanm, etc to use Yath instead of prove! Once Yath 2.0 and a non-dev version of the new Test-Harness are both available you can do this.
Yath working group (not an official name)
Garu, Preaction, Ilmari, and I came together to discuss Yath. A new goal for yath is to make it possible for Yath to send cpan testers reports. Garu wants a clear and easy way to make reports. Yath, specially with the above changes to Test-Harness should greatly simplify the process. (We also need a cpantesters plugin for Yath)
Ilmari helped me out with an Audit of the DBIc::Class components of Yath, as well as a short review of the schema where he fixed some index definitions. I am very grateful for this code review.
Preaction and I discussed creating a cpan central Yath server (formerly Yath::UI). This would be a very useful tool both for people running tests, and people trying to fix any issues the tests reveal.
Finally we are now trying to plan a Yath hackathon some time this year to all get together and improve Yath. If 2.0 is not released before the hackathon then the goal of the hackathon will be to get it there.
Other items
Many other things happened at the PTS. We had discussions about security and PAUSE/cpan. Metacpan and PAUSE both had significant work done to them, and both are much better today as a result.I did not actively participate in these improvements, so stay tuned for blogs from other attendees!
Monetary sponsors:
Booking.com, The Perl and Raku Foundation, Deriv, cPanel, Inc Japan Perl Association, Perl-Services, Simplelists Ltd, Ctrl O Ltd, Findus Internet-OPAC, Harald Joerg, Steven Schubiger.
In kind sponsors:
Fastmail, Grant Street Group, Deft, Procura, Healex GmbH, SUSE, Zoopla.
I am always flattered to be invited to the Perl Toolchain Summit, and reinvigorated in working on MetaCPAN each time.
Currently I am focused on building on the work I and others did last year in setting up Kubernetes for more of MetaCPAN (and other projects) to host on.
Last week I organised the Road map which was the first thing we ran through this morning. I was very fortunate to spend the day with Joel and between us we managed to setup:
- Hetzner (hosting company) volumes auto provisioning in the k8s cluster
- Postgres cluster version (e.g. with replication between nodes)
I had a few discussions with other projects interested in hosting and this has helped us start work on what we need to be able to provision and how.. especially with attached storage which has been some what of a challenge but we are heading towards a solution.
MetaCPAN indexing stopped... again.. because our bm-mc-01 server had disk issues (been going on for a couple of weeks). Whilst Oalders shutdown the server I switched over the puppet setup so bm-mc-02 was the primary postgres DB and cronjobs which will keep us going for a while longer, but does mean we are reliant on 2 servers which is not ideal from a failover point of view. Oalders has raised an issue with the hosting company... so we'll see how that works out.
Sponsors who make this possible Monetary sponsors: Booking.com, The Perl and Raku Foundation, Deriv, cPanel, Inc Japan Perl Association, Perl-Services, Simplelists Ltd, Ctrl O Ltd, Findus Internet-OPAC Harald Joerg, Steven Schubiger. In kind sponsors: Fastmail, Grant Street Group, Deft, Procura, Healex GmbH, SUSE, Zoopla.
Published by Anonymous on Saturday 18 May 2024 04:16
I just started learning Perl. I attempted to make a simple calculator that takes input from the command line. Input: 5 * 10
. Output: 50
. But instead, it just prints 5. Here's the code:
#!usr/bin/perl
use strict;
use warnings;
my $op = $ARGV[1];
my $outpt = eval("return $ARGV[0]"."$op"."$ARGV[2]");
print "$outpt"."\n";
Any advice would be appreciated.
I tried to input all as one string instead, but that resulted in terminal output no matches found. How should I fix the error.
Published by mauke on Friday 17 May 2024 21:48
perlfunc/stat: fix description of S_ENFMT and S_IFMT S_ENFMT properly belongs to the group of permission bits (like setuid/setgid), not file types. On systems that have it (like AIX), it can be set/cleared with chmod(). (In fact, it usually shares its value with S_ISGID because enforced locking is signaled by the combination of a non-executable file with the setgid bit set.) S_IFMT($mode) directly gives you one of the file types (S_IFREG, S_IFDIR, etc). You don't need to bit-and it further (especially not with the S_IS* functions), contrary to what the comment claims. (The confusion likely stems from the C side of things, where you'd do `mode & S_IFMT` to extract the file type from the mode bits, leading to code like `(mode & S_IFMT) == S_IFDIR`. But even then you could write `S_ISDIR(mode)` without any bit mask trickery.) Most of the symbols in the "S_IF* constants" section don't start with "S_IF", so change to "S_I* constants" everywhere. Most of the symbols in the "S_IF* functions" section don't start with "S_IF" (with the sole exception of S_IFMT, which is only a function in Perl; the C macro is a constant). (Historical note: This section label used to make more sense because it documented S_IFMODE and S_IFMT functions, but the former was just a typo for S_IMODE.)
Published by rwp0 on Friday 17 May 2024 13:45
`perlbook.pod`: Fix few leftovers The "Safari" reference redirects to oreilly.com anyway. It is also renamed: https://en.wikipedia.org/wiki/O%27Reilly_Media#O'Reilly_Online_Learning_(formerly_Safari_Books_Online)
Published by Grinnz on Friday 17 May 2024 13:42
perlsub: correct confusing references to local in my docs The docs for lexical variable declarations referenced 'local' as a mechanism to declare global variables in a couple instances, which is incorrect. 'local' only localizes global variables, it doesn't create or declare them in the common case where strict 'vars' is in effect.
Published by /u/oalders on Friday 17 May 2024 00:06
submitted by /u/oalders [link] [comments] |
Published on Thursday 16 May 2024 19:00
The Perl and Raku Conference (now in its 26th year) would not exist without sponsors. Above, you’ll see a screen shot from Curtis Poe’s Perl’s new object-oriented syntax is coming, but what’s next? talk at last year’s conference in Toronto. You may be wondering how you can add your organization’s logo to this year’s list. In the spirit of transparency, we are making our sponsorship prospectus public. Please share this article freely with friends, colleagues and decision makers so that we can reach as many new sponsors as possible.
This year the Perl and Raku Conference will be held in Las Vegas, Nevada on June 24-28, 2024. Conferences such as this provide tangible benefits to organizations which use Perl. Aside from the transfer of knowledge which attendees bring back to their place of work, on-site hackathons also contribute to the growth and maintenance of the software stack which so many companies have come to rely on. In 2022, for example, the hackathon focused on modernizing and improving support for Perl across various editors, allowing Perl developers to be even more productive than they have been in the past.
There are still opportunities to support this important, grassroots Open Source Software event. Events like these largely depend on sponsors in order to thrive.
This year, we are looking for corporate donations to offset the costs of feeding conference attendees. Each of these sponsorship opportunities comes with the following:
Sponsor a catered breakfast during one of the conference days
Sponsorship commitment: $3,500
Sponsor a catered snack break during one of the conference days.
Sponsorship commitment: $3,000
Sponsor a coffee break during one of the conference days.
Sponsorship commitment: $2,500
Please do let me know at what level you might be interested in contributing and we can begin the process of getting you involved in this very special event.
In order to get your logo on the “step and repeat” banner we would need to have finalized sponsorship and received logo assets by June 1st, so we’d love to help you start the process as soon as you’re ready.
For any questions or to begin the sponsorship process, please contact me via olaf@wundersolutions.com. I’ll be happy to answer any questions and walk you through the process. If you’d like to discuss sponsorship options which are greater or smaller than the offerings listed, I can also work with you on that. If you’re not ready to sponsor this event but would like to be included in future mailings, please reach out to me via email as well. I look forward to hearing from you!
In 2024 we expect to host over 100 attendees, but there is a hard cap of 150. If you’re thinking of attending, it’s best to secure your ticket soon.
Published by Bob Lied on Wednesday 15 May 2024 14:08
You and I have memories, longer than the road that stretches out ahead. Remember when refactoring was a Big Deal? Let's do some of that this week.
You are given an array of distinct integers, @ints.
Write a script to distribute the elements as
described below:
1) Put the 1st element of the given array to
a new array @arr1.
2) Put the 2nd element of the given array to
a new array @arr2.
Once you have one element in each arrays,
@arr1 and @arr2, then follow the rule below:
If the last element of the array @arr1 is greater
than the last element of the array @arr2, then
add the first element of the given array to @arr1,
otherwise to the array @arr2.
When done distribution, return the concatenated
arrays, @arr1 and @arr2.
@ints = (2, 1, 3, 4, 5)
Output: (2, 3, 4, 5, 1)
@arr1 = (2)
@arr2 = (1)
@arr1
is greater than the last element of @arr2
, so add 3 to @arr1 = (2, 3)
.@arr1
is greater than the last element of @arr2
, add 4 to @arr1 = (2, 3, 4)
@arr1
is again greater than the last element of @arr2
, add 5 to @arr1 = (2, 3, 4, 5)
@arr1 = (2, 3, 4, 5)
and @arr2 = (1)
(2, 3, 4, 5, 1)
.That's a very prescriptive specification and example. We could hardly do anything else.
sub distElem(@ints)
{
my @arr1 = shift @ints;
my @arr2 = shift @ints;
while ( defined(my $n = shift @ints) )
{
if ( $arr1[-1] > $arr2[-1] ) {
push @arr1, $n;
} else {
push @arr2, $n;
}
}
return [ @arr1, @arr2 ];
}
Perl notes:
@ints
array by shifting off one element at a time. Numbers could be zero, and we don't want that interpreted as false
, so the accurate check is to look for the undef
when the array becomes empty.It irks me to have the two variables named arr1
and arr2
. What is this, BASIC? It's a list of two arrays, so let's do that refactoring.
sub distElem(@ints)
{
my @arr = ( [shift @ints], [shift @ints] );
while ( defined(my $n = shift @ints) )
{
if ( $arr[0][-1] > $arr2[1][-1] ) {
push @{$arr[0]}, $n;
} else {
push @{$arr[1]}, $n;
}
}
return [ $arr[0]->@*, $arr[1]->@* ];
}
Perl notes:
push
needs to be an array, so the @{...}
turns the reference into an array. In the return statement, I use newer-style postfix de-referencing.Now I'm annoyed by that if
statement. We only have to choose between 0 and 1, and we have a condition that will be either true or false. Zero, one; false, true. Po-tay-to, po-tah-to. Let's use that condition to make an index.
sub distElem(@ints)
{
my @arr = ( [shift @ints], [shift @ints] );
while ( defined(my $n = shift @ints) )
{
my $which = ( $arr[0][-1] <= $arr[1][-1] );
push @{$arr[$which]}, $n;
}
return [ $arr[0]->@*, $arr[1->@*} ];
}
Perl notes:
>
to <=
so that the array order is the same.Introducing the $which
variable seems arbitrary. Let's put that in-line.
sub distElem(@ints)
{
my @arr = ( [shift @ints], [shift @ints] );
while ( defined(my $n = shift @ints) )
{
push @{$arr[ $arr[0][-1] <= $arr[1][-1 ]}, $n;
}
return [ $arr[0]->@*, $arr[1->@*} ];
}
Why am I chewing up the @ints
array with shifts? Let's just iterate over it.
sub distElem(@ints)
{
my @arr = ( [shift @ints], [shift @ints] );
push @{$arr[ $arr[0][-1] <= $arr[1][-1 ]}, $_ for @ints;
return [ $arr[0]->@*, $arr[1->@*} ];
}
One last thing: can we make it do reasonable things when the @ints
array has 0 or 1 elements? Currently, that inital shift to initialize @arr
would put an undef
value into the lists. Let's account for the possibility.
sub distElem(@ints)
{
my @arr = ( [ (shift @ints) // () ], [ (shift @ints) // () ] );
push @{$arr[ ( $arr[0][-1] <= $arr[1][-1] ) ]}, $_ for @ints;
return [ $arr[0]->@*, $arr[1]->@* ];
}
Perl notes:
shift
on an empty array will yield undef
, but we want an empty list in that case.//
operator is really useful for checking defined-ness. In the old days, code was littered with if (defined(...))
tests.That was the process I used to get from 11 lines to 3. Of course, there were unit tests executed at every step. The final code, including tests is in GitHub
We're happy to confirm the venue and date of this year's London Perl & Raku Workshop.
This year's workshop will be held at The Trampery, at Old Street. A dedicated modern event space in central London. We have hired both The Ballroom and The Library; allowing us to run a main track for up to 160 attendees, and second smaller track for up to 35 attendees.
The Trampery in Old Street is located a two minute walk from the Northern Line's Old Street tube station in central London. The Northern Line has stops at most of the major train stations in London, or trivial links to others, so we recommend taking the tube to get to the venue.
If you haven't already, please signup and submit talks using the official workshop site: https://act.yapc.eu/lpw2024/
Thanks to this year's sponsors, without whom LPW would not happen:
If you would like to sponsor LPW then please have a look at the options here: https://act.yapc.eu/lpw2024/sponsoring.html
Published by /u/SamuchRacoon on Monday 13 May 2024 13:03
I’m sorry if the text is strange, but I cannot upload it with my laptop.
I want to repeat a process for every key in a hash, with numeric keys. So there are 3 possibilities, with 3 if, and each one compares the value of the index of an array, so that if that position eq to "sp", "sp2" or "sp3" it will search in a document some value so then it can be printed.
It doesn´t work and every times gives me only one value, i would like to get the values that correspond with the hash.
For example the hash could be %grupos=(1,'A',2,'G',3,'J')
and the array @ hibridaciones=("sp","sp2",sp3")
The document .txt (simplified) is:
HS0.32
CS0,77
CD0.62
CT0,59
C10,77
C20,62
C30,59
OS0.73
OD0,6
O10,73
O20,6
NS0.75
The code is:
@hibridaciones=("sp","sp2",sp3") %grupos=(1,'A',2,'G',3,'J') open (covalencia,"<", "cov.txt") or die "$!\n"; print keys %grupos; keys %grupos; foreach my $z (keys %grupos) { print "\n$z\n"; if (@hibridaciones[my $z-1] eq "sp") { while (my $line = <covalencia>) { if ( $line=~/^C1/) { $line =~s/C1//; $radio=$line; print "\n$radio"; } } } if (@hibridaciones[my $z-1] eq "sp2") { while (my $line = <covalencia>) { if ($line=~/^C2/) { $line =~s/C2//; $radio=$line; print "\n$radio"; } } } if (@hibridaciones[my $z-1] eq "sp3") { while (my $line = <covalencia>) { if ($line=~/^C3/) { $line =~s/C3//; $radio=$line; print "\n$radio"; } } } } close (covalencia);@hibridaciones=("sp","sp2",sp3") %grupos=(1,'A',2,'G',3,'J') open (covalencia,"<", "cov.txt") or die "$!\n"; print keys %grupos; keys %grupos; foreach my $z (keys %grupos) { print "\n$z\n"; if (@hibridaciones[my $z-1] eq "sp") { while (my $line = <covalencia>) { if ( $line=~/^C1/) { $line =~s/C1//; $radio=$line; print "\n$radio"; } } } if (@hibridaciones[my $z-1] eq "sp2") { while (my $line = <covalencia>) { if ($line=~/^C2/) { $line =~s/C2//; $radio=$line; print "\n$radio"; } } } if (@hibridaciones[my $z-1] eq "sp3") { while (my $line = <covalencia>) { if ($line=~/^C3/) { $line =~s/C3//; $radio=$line; print "\n$radio"; } } } } close (covalencia);
Originally published at Perl Weekly 668
Hi there,
The latest Perl Steering Council weekly updates about the good progress in preparation of release of Perl v5.40. I can't wait to get my hand dirty with the new features.
London Perl Workshop is making good progress thanks to the hard work of Lee Johnson. As per the official website, we now have a Diamond Sponsor. I am hoping venue would be finalised soon. I would urge all Perl fans to register your interest in the event so that the organiser can plan the event better.
The upconing event, The Perl and Raku Conference in Las Vegas, is in demand. I get to hear a lot of preparation is underway to make it memorable experience for all attendees. I am going to miss the fun, unfortunately. I hope to join you all online if it is available.
Last but not least, you take extra care of yourself and your loved ones. Enjoy and celebrate Perl as always.
--
Your editor: Mohammad Sajid Anwar.
Good news is shared that Perl v5.40 is likely to be released on time in May. Hurray !!!
Nice to hear the work done by CPANSec Group. We are happy to see members are actively working on the security aspect.
Interesting topic brought to the discussion table with regard to the use of DBIx::Class and it's family. It is thorough discussion and not just scratch the surface.
Calendar is one topic that has been discussed plenty of times and we have loads of different implmentation available on CPAN. Saif is bringing a new flavour, go check it out.
The Weekly Challenge by Mohammad Sajid Anwar will help you step out of your comfort-zone. We pick one champion at the end of the month from among all of the contributors during the month.
Welcome to a new week with a couple of fun tasks "Bitwise OR" and "Distribute Elements". If you are new to the weekly challenge then why not join us and have fun every week. For more information, please read the FAQ.
Enjoy a quick recap of last week's contributions by Team PWC dealing with the "Magic Number" and "Number Game" tasks in Perl and Raku. You will find plenty of solutions to keep you busy.
A new CPAN module introduced Data::Show. Time to explore more about it. Thanks for sharing.
Smart match of Raku is really cool. The post shares the use of smart match. Highly recommended.
I love the varieties of different level of solutions. Start with simple and then move upward to make it more elegant. Great work.
Ever wanted to implement Z- operator in Perl? Well it is already done and shared. Just check it out yourself.
My personal favourite PDL is in the game again. Thanks for sharing knowledge with us.
Reduction operator of Raku is one of the most powerful operator. Please checkout the post to see how it can be used.
Handy Raku REPL is showing off the power. You really don't want to skip it. Thanks for sharing.
Another Raku fan talking about rotor of Raku. I wonder if this can be reproduced this in Perl?
Master of one-liner in Perl, sharing experimental for_list. Time to explore more about it soon. Well done and keep it up.
Task analysis is the top level and very engaging. Thanks for sharing the knowledge with us.
Short and compact solutions in Perl, Raku and Python. Plenty to keep you busy. You get to listen to music as bonus.
Peter finally gave in and created one-liner in Perl. It is so much fun to see how powerful it is.
Well documented solutions with smart use of CPAN module. Well done, keep it up great work.
I noticed the zip6 is mentioned in the blog post but in code, pairwise is used. Interesting, zip6 is new to me, though.
One liner in Python and PostScript. Bonus for this week is the introduction to Crystal. Keep it up great work.
Is it possible to have multiple return types in Python? I didn't know that, I liked how it is perfectly used here. Thanks for sharing the magic with us.
Great CPAN modules released last week;
StackOverflow Perl report.
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(C) Copyright Gabor Szabo
The articles are copyright the respective authors.
Published by /u/niceperl on Sunday 12 May 2024 07:43
Published by Unknown on Sunday 12 May 2024 09:43
These are the five most rated questions at Stack Overflow last week.
Between brackets: [question score / answers count]
Build date: 2024-05-12 07:32:36 GMT
Each week Mohammad S. Anwar sends out The Weekly Challenge, a chance for all of us to come up with solutions to two weekly tasks. My solutions are written in Python first, and then converted to Perl. It's a great way for us all to practice some coding.
You are given two arrays of integers of same size, @x
and @y
.
Write a script to find the magic number that when added to each elements of one of the array gives the second array. Elements order is not important.
For input via the command line, I take a list of integers and then split the list in two. Calling the Python function directly takes two list.
For this task I numerically sort the two lists x
and y
. I then calculate the different between the first values in each list, and store this as diff
.
I then loop through each position in the list to ensure the difference between the integers in that position in each list is diff
. If it isn't, I exit early.
def magic_number(x: list, y: list) -> int | None:
x = sorted(x)
y = sorted(y)
diff = y[0] - x[0]
for i in range(len(x)):
if y[i] - x[i] != diff:
return None
return diff
$ ./ch-1.py 3 7 5 9 5 7
2
$ ./ch-1.py 1 2 1 5 4 4
3
$ ./ch-1.py 2 5
3
You are given an array of integers, @ints
, with even number of elements.
Write a script to create a new array made up of elements of the given array. Pick the two smallest integers and add it to new array in decreasing order i.e. high to low. Keep doing until the given array is empty.
This is relatively straight forward, so doesn't need much explanation. For this task, I sort the list and then swap each pairs of numbers (1st and 2nd, 3rd and 4th, etc).
Both Python and Perl support the x, y = y, x
syntax to swap numbers without using a temporary value.
def numbers_game(ints: list) -> list:
ints = sorted(ints)
for i in range(0, len(ints), 2):
ints[i], ints[i+1], = ints[i+1], ints[i]
return ints
$ ./ch-2.py 2 5 3 4
(3, 2, 5, 4)
$ ./ch-2.py 9 4 1 3 6 4 6 1
(1, 1, 4, 3, 6, 4, 9, 6)
$ ./ch-2.py 1 2 2 3
(2, 1, 3, 2)
Published by Makoto Nozaki on Thursday 09 May 2024 19:21
TL;DR We just finished intern selection for this year’s Outreachy program. We got more projects and more applicants than the previous years, which made the selection hard in a good way.
Continuing our annual tradition, The Perl and Raku foundation is involved in the Outreachy program which provides internships to people subject to systemic bias and impacted by underrepresentation.
We have just finished the intern selection process, which turned out to be harder compared to the previous years. I’ll explain the reasons below.
Each year, we call for project ideas from the Perl/Raku community. Project proposer is required to commit to mentoring an intern from May to August. Given the significant commitment involved, it’s not uncommon for us to find suitable projects.
Fortunately, this year, we got two promising project proposals. The Foundation’s financial situation did not allow us to sponsor both projects, so we had to make the tough decision to support only one project.
After careful consideration, the Board has elected to sponsor Open Food Fact’s Perl project, titled “Extend Open Food Facts to enable food manufacturers to open data and improve food product quality.”
Having more projects means we were able to attract more intern candidates. Across the two projects, more than 50 people showed interest and initiated contributions. Among them, 21 individuals actually created pull requests before the selection process.
Needless to say, it's hard work for the mentors to help dozens of candidates. They taught these intern candidates how to code and guided them through creating pull requests. On the applicants’ side, I am amazed that they worked hard to learn Perl and became proficient enough to create pull requests and make real improvements to the systems.
After the contribution process, we got an application from 14 people. It was obviously hard for the mentors to select one from so many good applicants. In the next post, Stéphane Gigandet will introduce our new intern to the community.
I wish all the best to the mentors, Stéphane and Alex, and our new intern.
"In the journey to understand Perl better, I wanted to know what are its most wide applications, one of them being a web scraper. It's because Perl's strong support for regular expressions and built-in text manipulation functions make it well-suited for tasks like web scraping, where parsing and transforming text are essential. I took inspiration from various web scraping projects available on the internet to gain insights into the process and developed a lyrics scraper."
"I'm currently diving into Perl, and I see this as a fantastic chance to enrich my coding skills. I've thoroughly enjoyed immersing myself in it and have had the opportunity to explore various technologies like Docker and more."
"I have had the opportunity to experience Perl firsthand and have come to appreciate its significance in web development, on which I have worked. During my second year, I was searching for popular languages in backend development and found out about Perl, whose syntax was somewhat like C and Python. I didn't have any previous experience working with Perl, but now I have gained a deep understanding of its importance and impact on backend development and data processing."
"In this pull request, I made a significant stride in improving the quality and maintainability of our Perl codebase by integrating Perl::Critic, a powerful static code analysis tool."
"I've learned a whole lot about Perl and some of its frameworks such as Dancer2 (a surprisingly simple framework I've come to fall in love with)."
Welcome to “What’s new on CPAN”, a curated look at last month’s new CPAN uploads for your reading and programming pleasure. Enjoy!
Published by alh on Monday 06 May 2024 19:42
Tony writes:
``` [Hours] [Activity] 2024/02/01 Thursday
2.50
2024/02/02 Friday 0.72 #21915 review, testing, comments
0.97
2024/02/05 Monday 0.25 github notifications 0.08 #21885 review updates and approve 0.57 #21920 review and comment 0.08 #21921 review and approve 0.12 #21923 review and approve 0.08 #21924 review and approve 0.08 #21926 review and approve 0.67 #21925 review and comments
3.93
2024/02/06 Tuesday 0.23 #21925 comment 0.52 review coverity scan report, reply to email from jkeenan 0.27 #21927 review and comment 0.08 #21928 review and approve
1.18
2024/02/07 Wednesday 0.25 github notifications 0.52 #21935 review, existing comments need addressing
2.89
2024/02/08 Thursday 0.40 #21927 review and approve 0.23 #21935 review, check each comment has been addressed, approve 0.45 #21937 review and approve 0.15 #21938 review and comment 0.10 #21939 review and approve 0.13 #21941 review and approve 0.10 #21942 review and approve 0.08 #21943 review and approve 0.07 #21945 review and approve 0.17 #21877 look into CI failures, think I found problem, push probable fix 0.18 #21927 make a change to improve pad_add_name_pvn() docs, testing, push for CI 2.20 #21877 performance test on cygwin, try to work up a
4.26
2024/02/12 Monday 0.60 #18606 fix minor issue pointed out by mauke, testing 0.40 github notifications 0.08 #21872 review latest changes and approve 0.08 #21920 review latest changes and approve 1.48 #21877 debugging test 0.30 #21524 comment on downstream ticket
3.21
2024/02/13 Tuesday 0.35 #21915 review, brief comment 0.25 #21983 review and approve 0.03 #21233 close 0.28 #21878 comment 0.08 #21927 check CI results and make PR 21984 0.63 #21877 debug failing CI 0.27 #21984 follow-up 0.58 #21982 review, testing, comments
2.79
2024/02/14 Wednesday 1.83 #21958 testing, finally reproduce, debugging and comment 0.08 #21987 review discussion and briefly comment 0.08 #21984 apply to blead 0.22 #21977 review and approve 0.12 #21988 review and approve 0.15 #21990 review and approve 0.82 #21550 probable fix, build tests 0.38 coverity scan follow-up 1.27 #21829/#21558 (related to 21550) debugging
5.60
2024/02/15 Thursday 0.15 github notifications 0.08 #21915 review updates and approve 2.17 #21958 debugging, research, long comment 0.58 #21958 testing, follow-up
3.10
2024/02/19 Monday 0.88 #21161 review comment and reply, minor change, testing, force push 0.23 #22001 review and comment 0.30 #22002 review and comment 0.12 #22004 review and comment 0.28 #22005 review and approve 0.32 #21993 testing, review changes 1.95 #21661 review comments on PR and fixes, review code and
4.08
2024/02/20 Tuesday 0.35 github notifications 0.08 #22010 review and approve 0.08 #22007 review and approve with comment 0.60 #22006 review, research and approve with comment 0.08 #21989 review and approve 0.58 #21996 review, testing, comment 0.22 #22009 review and approve 0.50 #21925 review latest updates and approve
3.54
2024/02/21 Wednesday 0.18 #22011 fixes 0.80 #21683 refactoring
2.78
2024/02/22 Thursday 0.38 #22007 review and comment 0.70 #21161 apply to blead, perldelta as PR22017 1.75 smoke report checks: testing win32 gcc failures 0.27 #22007 review updates and approve
4.25
2024/02/26 Monday 2.10 look over smoke reports, debug PERLIO=stdio failure on mac
3.48
2024/02/27 Tuesday 0.08 #22029 review and apply to blead 0.27 #22024 review and approve 0.33 #22026 review and approve 0.08 #22027 review and approve 0.10 #22028 review and approve 0.08 #22030 review and comment, conditionally approve 0.25 #22033 review, comments and approve 0.08 #22034 review and approve 0.17 #22035 review and comment
2.22
2024/02/28 Wednesday 0.38 github notifications 0.52 #22040 review discussion, research and comment 0.13 #22043 review and approve 0.12 #22044 review and approve 0.72 #22045 review, research, comment and approve 0.13 #22046 review, research and approve
3.55
2024/02/29 Thursday 0.15 #21966 review update and approve 1.18 #21877 debugging
1.46
Which I calculate is 55.79 hours.
Approximately 70 tickets were reviewed or worked on, and 5 patches were applied. ```
Published by Unknown on Saturday 04 May 2024 22:46
Published by Makoto Nozaki on Friday 03 May 2024 19:49
I am pleased to announce that The Perl and Raku Foundation sponsored the Perl Toolchain Summit 2024 as a Platinum Sponsor.
The Perl Toolchain Summit (PTS) is an annual event where they bring together the volunteers who work on the tools and modules at the heart of Perl and the CPAN ecosystem. The PTS gives them 4 days to work together on these systems, with all their fellow volunteers to hand.
The event successfully concluded in Lisbon, Portugal at the end of April 2024.
If you or your company is willing to help the future PTS events, you can get in touch with the PTS team. Alternatively, you can make a donation to The Perl and Raku Foundation, which is a 501(c)(3) organization.
Published by perlancar on Wednesday 01 May 2024 02:38
dist | author | abstract | date |
---|---|---|---|
AI-Ollama-Client | CORION | Client for AI::Ollama | 2024-04-05T09:15:33 |
Acme-CPANModules-BPOM-FoodRegistration | PERLANCAR | List of modules and utilities related to Food Registration at BPOM | 2024-04-27T00:06:16 |
Acme-CPANModules-JSONVariants | PERLANCAR | List of JSON variants/extensions | 2024-04-29T00:05:46 |
Alien-NLOpt | DJERIUS | Build and Install the NLOpt library | 2024-04-28T00:59:11 |
Alien-onnxruntime | EGOR | Discover or download and install onnxruntime (ONNX Runtime is a cross-platform inference and training machine-learning accelerator.) | 2024-04-17T22:03:45 |
AnyEvent-I3X-Workspace-OnDemand | WATERKIP | An I3 workspace loader | 2024-04-12T18:33:21 |
App-papersway | SPWHITTON | PaperWM-like window management for Sway/i3wm | 2024-04-12T08:18:00 |
App-sort_by_comparer | PERLANCAR | Sort lines of text by a Comparer module | 2024-04-16T00:06:00 |
App-sort_by_example | PERLANCAR | Sort lines of text by example | 2024-04-20T00:05:10 |
App-sort_by_sorter | PERLANCAR | Sort lines of text by a Sorter module | 2024-04-17T00:05:42 |
App-sort_by_sortkey | PERLANCAR | Sort lines of text by a SortKey module | 2024-04-24T00:06:38 |
Arithmetic-PaperAndPencil | JFORGET | simulating paper and pencil techniques for basic arithmetic operations | 2024-04-22T19:57:44 |
Bencher-Scenario-ExceptionHandling | PERLANCAR | Benchmark various ways to do exception handling in Perl | 2024-04-13T00:05:36 |
CPAN-Requirements-Dynamic | LEONT | Dynamic prerequisites in meta files | 2024-04-27T15:17:57 |
CSAF | GDT | Common Security Advisory Framework | 2024-04-23T21:49:42 |
CXC-DB-DDL | DJERIUS | DDL for table creation, based on SQL::Translator::Schema | 2024-04-04T16:24:13 |
Captcha-Stateless-Text | HIGHTOWE | stateless, text-based CAPTCHAs | 2024-04-17T21:19:21 |
Carp-Object | DAMI | a replacement for Carp or Carp::Clan, object-oriented | 2024-04-28T17:58:22 |
Carp-Patch-OutputToBrowser | PERLANCAR | Output stacktrace to browser as HTML instead of returning it | 2024-04-25T00:05:19 |
Catalyst-Plugin-Flash | ARISTOTLE | put values on the stash of the next request | 2024-04-09T05:06:19 |
Comparer-date_in_text | PERLANCAR | Compare date found in text (or text asciibetically, if no date is found) | 2024-04-18T00:05:43 |
Crypt-Passphrase-Bcrypt-Compat | LEONT | A bcrypt encoder for Crypt::Passphrase | 2024-04-08T14:24:10 |
DBD-Mock-Session-GenerateFixtures | UXYZAB | When a real DBI database handle ($dbh) is provided, the module generates DBD::Mock::Session data. Otherwise, it returns a DBD::Mock::Session object populated with generated data. This not a part form DBD::Mock::Session distribution just a wrapper around it. | 2024-04-29T18:25:02 |
Data-Dumper-UnDumper | BIGPRESH | load Data::Dumper output, including self-references | 2024-04-25T21:42:30 |
Data-MiniDumpX | PERLANCAR | A simplistic data structure dumper (demo for Plugin::System) | 2024-04-14T00:06:13 |
DateTime-Format-PDF | SKIM | PDF DateTime Parser and Formatter. | 2024-04-01T09:23:07 |
Devel-Confess-Patch-UseDataDumpHTMLCollapsible | PERLANCAR | Use Data::Dump::HTML::Collapsible to stringify reference | 2024-04-26T00:05:16 |
Devel-Confess-Patch-UseDataDumpHTMLPopUp | PERLANCAR | Use Data::Dump::HTML::PopUp to stringify reference | 2024-04-28T00:06:05 |
Dist-Build | LEONT | A modern module builder, author tools not included! | 2024-04-26T10:50:10 |
Dist-Zilla-Plugin-DistBuild | LEONT | Build a Build.PL that uses Dist::Build | 2024-04-26T10:55:35 |
Dist-Zilla-Plugin-DynamicPrereqs-Meta | LEONT | Add dynamic prereqs to to the metadata in our Dist::Zilla build | 2024-04-27T15:50:03 |
ExtUtils-Builder | LEONT | An overview of the foundations of the ExtUtils::Builder Plan framework | 2024-04-25T12:14:45 |
ExtUtils-Builder-Compiler | LEONT | Portable compilation | 2024-04-25T13:18:11 |
JSON-Ordered-Conditional | LNATION | A conditional language within an ordered JSON struct | 2024-04-06T06:47:37 |
JSON-ToHTML | ARISTOTLE | render JSON-based Perl datastructures as HTML tables | 2024-04-09T04:28:11 |
Knowledge | RSPIER | a great new dist | 2024-04-27T11:13:53 |
Log-Any-Simple | MATHIAS | A very thin wrapper around Log::Any, using a functional interface that dies automatically when you log above a given level. | 2024-04-24T19:51:03 |
Mo-utils-Country | SKIM | Mo country utilities. | 2024-04-11T13:41:33 |
Mo-utils-Time | SKIM | Mo time utilities. | 2024-04-12T14:28:06 |
Mo-utils-TimeZone | SKIM | Mo timezone utilities. | 2024-04-03T16:34:52 |
Mojolicious-Plugin-Authentication-OIDC | TYRRMINAL | OpenID Connect implementation integrated into Mojolicious | 2024-04-25T19:27:09 |
Mojolicious-Plugin-Cron-Scheduler | TYRRMINAL | Mojolicious Plugin that wraps Mojolicious::Plugin::Cron for job configurability | 2024-04-16T11:48:54 |
Mojolicious-Plugin-Migration-Sqitch | TYRRMINAL | Run Sqitch database migrations from a Mojo app | 2024-04-30T15:37:52 |
Mojolicious-Plugin-Module-Loader | TYRRMINAL | Automatically load mojolicious namespaces | 2024-04-19T14:09:36 |
Mojolicious-Plugin-ORM-DBIx | TYRRMINAL | Easily load and access DBIx::Class functionality in Mojolicious apps | 2024-04-03T13:32:06 |
Mojolicious-Plugin-SendEmail | TYRRMINAL | Easily send emails from Mojolicious applications | 2024-04-01T20:40:24 |
Mojolicious-Plugin-Sessionless | TYRRMINAL | Installs noop handlers to disable Mojolicious sessions | 2024-04-16T12:45:37 |
MooX-Pack | LNATION | The great new MooX::Pack! | 2024-04-20T01:52:17 |
Net-Async-OpenExchRates | VNEALV | Interaction with OpenExchangeRates API | 2024-04-20T11:46:28 |
Net-EPP-Server | GBROWN | A simple EPP server implementation. | 2024-04-08T09:38:21 |
Number-Iterator | LNATION | The great new Number::Iterator! | 2024-04-18T19:45:31 |
Parallel-TaskExecutor | MATHIAS | Cross-platform executor for parallel tasks executed in forked processes | 2024-04-13T20:02:27 |
Plack-App-Login-Request | SKIM | Plack application for request of login information. | 2024-04-29T14:23:02 |
Sah-SchemaBundle-Business-ID-BCA | PERLANCAR | Sah schemas related to BCA (Bank Central Asia) bank | 2024-04-23T00:05:53 |
Sah-SchemaBundle-Business-ID-Mandiri | PERLANCAR | Sah schemas related to Mandiri bank | 2024-04-30T00:05:43 |
Sah-SchemaBundle-Comparer | PERLANCAR | Sah schemas related to Comparer | 2024-04-21T00:05:30 |
Sah-SchemaBundle-Path | PERLANCAR | Schemas related to filesystem path | 2024-04-01T00:06:15 |
Sah-SchemaBundle-Perl | PERLANCAR | Sah schemas related to Perl | 2024-04-02T00:05:40 |
Sah-SchemaBundle-SortKey | PERLANCAR | Sah schemas related to SortKey | 2024-04-22T00:06:02 |
Sah-SchemaBundle-Sorter | PERLANCAR | Sah schemas related to Sorter | 2024-04-03T00:14:57 |
Sah-Schemas-Sorter | PERLANCAR | Sah schemas related to Sorter | 2024-04-03T00:05:43 |
Seven | LNATION | The great new Seven! | 2024-04-13T03:30:11 |
Sort-Key-SortKey | PERLANCAR | Thin wrapper for Sort::Key to easily use SortKey::* | 2024-04-04T00:05:05 |
SortExample-Color-Rainbow-EN | PERLANCAR | Ordered list of names of colors in the rainbow, in English | 2024-04-05T00:06:12 |
SortKey-Num-pattern_count | PERLANCAR | Number of occurrences of string/regexp pattern as sort key | 2024-04-06T00:05:41 |
SortKey-Num-similarity | PERLANCAR | Similarity to a reference string as sort key | 2024-04-08T00:05:21 |
SortKey-date_in_text | PERLANCAR | Date found in text as sort key | 2024-04-19T00:05:23 |
SortSpec | PERLANCAR | Specification of sort specification | 2024-04-09T00:05:37 |
SortSpec-Perl-CPAN-ChangesGroup-PERLANCAR | PERLANCAR | Specification to sort changes group heading PERLANCAR-style | 2024-04-10T00:05:24 |
Sorter-from_comparer | PERLANCAR | Sort by comparer generated by a Comparer:: module | 2024-04-11T00:05:17 |
Sorter-from_sortkey | PERLANCAR | Sort by keys generated by a SortKey:: module | 2024-04-12T00:05:58 |
Sqids | MYSOCIETY | generate short unique identifiers from numbers | 2024-04-06T10:43:27 |
TableData-Business-ID-BPOM-FoodAdditive | PERLANCAR | Food additives in BPOM | 2024-04-10T11:10:00 |
Tags-HTML-Image | SKIM | Tags helper class for image presentation. | 2024-04-20T13:32:39 |
Tags-HTML-Login-Request | SKIM | Tags helper for login request. | 2024-04-29T11:23:37 |
Test2-Tools-MIDI | JMATES | test MIDI file contents | 2024-04-09T23:42:34 |
Tiny-Prof | TIMKA | Perl profiling made simple to use. | 2024-04-26T07:19:38 |
Web-Async | TEAM | Future-based web+HTTP handling | 2024-04-23T16:50:24 |
YAML-Ordered-Conditional | LNATION | A conditional language within an ordered YAML struct | 2024-04-06T06:05:51 |
kraken | PHILIPPE | api.kraken.com connector | 2024-04-05T09:11:35 |
papersway | SPWHITTON | PaperWM-like window management for Sway/i3wm | 2024-04-12T07:52:39 |
Number of new CPAN distributions this period: 81
Number of authors releasing new CPAN distributions this period: 26
Authors by number of new CPAN distributions this period:
No | Author | Distributions |
---|---|---|
1 | PERLANCAR | 30 |
2 | TYRRMINAL | 7 |
3 | LEONT | 7 |
4 | SKIM | 7 |
5 | LNATION | 5 |
6 | MATHIAS | 2 |
7 | SPWHITTON | 2 |
8 | DJERIUS | 2 |
9 | ARISTOTLE | 2 |
10 | PHILIPPE | 1 |
11 | JFORGET | 1 |
12 | VNEALV | 1 |
13 | RSPIER | 1 |
14 | UXYZAB | 1 |
15 | WATERKIP | 1 |
16 | GBROWN | 1 |
17 | CORION | 1 |
18 | EGOR | 1 |
19 | TIMKA | 1 |
20 | TEAM | 1 |
21 | BIGPRESH | 1 |
22 | HIGHTOWE | 1 |
23 | DAMI | 1 |
24 | MYSOCIETY | 1 |
25 | JMATES | 1 |
26 | GDT | 1 |
Welcome to “What’s new on CPAN”, a curated look at last month’s new CPAN uploads for your reading and programming pleasure. Enjoy!
Published by Ted James on Monday 29 April 2024 07:12
Published by Unknown on Sunday 28 April 2024 09:07
Published by Amber Krawczyk on Saturday 27 April 2024 11:36
We hope you are coming to [The Perl and Raku Conference[(https://tprc.us/) in Las Vegas June 24-28! Plans are underway for a wonderful TPRC. But a conference of this type is only possible because of volunteers who give their time and expertise to plan, promote, and execute every detail. We need volunteers! You may have already volunteered to speak at the conference; if so, wonderful! If you are not presenting (or even if you are), there are many ways to help. We need people to set up and take down, to run the registration desk, to serve as room monitors, to help record the talks, and to just be extra hands. If you can spare some of your time for the sake of the conference, please fill out a volunteer form at https://tprc.us/tprc-2024-las/volunteer/ . We also welcome spouses and friends of attendees who might be coming along to Las Vegas to share the experience. We are offering TPRC "companion" tickets, for access to the social parts of the conference (food, drink, parties) but not the technical. Volunteers of at least one complete day, who sign up before the conference, will have companion access "comped". If you have questions about volunteering, please contact our TPRC Volunteer Coordinator: Sarah Gray sarah.gray@pobox.com
Published by Saif Ahmed on Friday 26 April 2024 15:18
Another Grant Application from a key Raku develoer, Stefan Seifert. A member of the Raku Steering Council, Stefan is also an author of several Perl 5 modules including Inline::Python and (of course) Inline::Perl6. This Grant is to help advance AST or Abstract Syntax Tree. This is integral to Raku internals and allows designing and implementation of new language components, that can be converted into bytecode for execution by the interpreteter or "virtual machine" more easily that trying to rewrite the interpretter. Here is an excellent intro by Elizabeth Mattijsen
There is a grant called RakuAST granted to Johnathan Worthington that is still listed as running. Sadly Johnathan has moved on and is no longer actively developing the Rakudo core. However the goal of his grant is still worthy as it is one of the strategic initiatives providing numerous benefits to the language. I have in fact already taken over his work on RakuAST and over the last two years have pushed some 450+ commits which led to hundreds of spectests to pass. This work was done in my spare time which was possible because I had a good and reliable source of income and could at times sneak in some Raku work into my dayjob. I can no longer claim that Raku is in any way connected to my day job and time invested in Raku comes directly out of the pool that should ensure my financial future. In other words, there's a real cost for me and I'd like to ask for this to be offset by way of a grant.
This is mostly directly taken from the RakuAST grant proposal as the goal stays the same:
An AST can be thought of as a document object model for a programming language. The goal of RakuAST is to provide an AST that is part of the Raku language specification, and thus can be relied upon by the language user. Such an AST is a prerequisite for a useful implementation of macros that actually solve practical problems, but also offers further powerful opportunities for the module developer. For example:
RakuAST will also become the initial internal representation of Raku programs used by Rakudo itself. That in turn gives an opportunity to improve the compiler. The frontend compiler architecture of Rakudo has changed little in the last 10 years. Naturally, those working on it have learned a few things in that time, and implementing RakuAST provides a chance to fold those learnings into the compiler. Better static optimization, use of parallel processing in the compiler, and improvements to memory and time efficiency are all quite reasonable expectations. We have already seen that the better internal structure fixes a few long standing bugs incidentally. However, before many of those benefits can be realized, the work of designing and implementing RakuAST, such that the object model covers the entire semantic and declarational space of the language, must take place. This grant focuses on that work.
Considering the amount of work these items already will be, I would specifically exclude work targeted at synthetic AST generation, designs for new macros based on this AST, and anything else that is not strictly necessary to reach the goal of the RakuAST compiler frontend becoming the default.
For the test and spectest suites I would continue my tried and proven model of picking the next failing test file and making fixes until it passes. Based on current velocity this will take around 6 months. However there's hope that some community members will return from their side projects and chime in.
$10,000 for an estimated 200 hours of work.
I have been involved in Rakudo development since 2014 when I started development of Inline::Perl5 which brings full two-way interoperability between Raku and Perl. Since then I have helped with every major effort in Rakudo core development like the Great List Refactor, the new dispatch mechanism and full support for unsigned native integers. I have fixed hundreds of bugs in MoarVM including garbage collection issues, race conditions and bugs in the specializer. I have made NativeCall several orders of magnitude faster by writing a special dispatcher and support for JIT compiling native calls. I replaced a slow and memory hungry MAST step in the compilation process by writing bytecode directly, have written most of Rakudo's module loading and repository management code and in general have done everything I could to make Rakudo production worthy. I have also been a member of the Raku Steering Council since its inception.
Elizabeth Mattijsen, Geoffrey Broadwell, Nick Logan, Richard Hainsworth
At the Koha Hackfest I had several discussions with various colleagues about how to improve the way plugins and hooks are implemented in Koha. I have worked with and implemented various different systems in my ~25 years of Perl, so I have some opinions on this topic.
When you have some generic piece of code (eg a framework or a big application that will be used by different user groups (like Koha)), people will want to add custom logic to it. But this custom logic will probably not make sense to every user. And you probably don't want all of these weird adaptions in the core code. So you allow users to write their weird adaptions in Plugins, which will be called via Hooks in the core code base. This patter is used by a lot of software, from eg mod_perl/Apache, Media Players to JavaScript frontend frameworks like Vue.
Generally, there are two kinds of Hook philosophies: Explicit Hooks, where you add explicit calls to the hook to the core code; and Implicit Hooks, where some magic is used to call Plugins.
Explicit Hooks are rather easy to understand and implement:
package MyApp::Model::SomeThing;
method create ($args) {
$self->call_hook("pre_create", $args);
my $item = $self->resultset("SomeThing")->create( $args );
$self->call_hook("post_create", $args, $item);
return $item;
}
So you have a method create
which takes some $args
. It first calls the pre_create
hook, which could munge the $args
. Then it does what the Core implementation wants to do (in this case, create a new item in the database). After that it calls the post_create
hook which could do further stuff, but now also has the freshly created database row available.
The big advantage of explicit hooks is that you can immediately see which hook is called when & where. The downside is of course that you have to pepper your code with a lot of explicit calls, which can be very verbose, especially once you add error handling and maybe a way for the hook to tell the core code to abort processing etc. Our nice, compact and easy to understand Perl code will end up looking like Go code (where you have to do error handling after each function call)
Implicit hooks are a bit more magic, because the usually do not need any adaptions to the core code:
package MyApp::Model::SomeThing;
method create ($args) {
my $item = $self->resultset("Foo")->create( $args );
return $item
}
There are lots of ways to implement the magic needed.
One well-known one is Object Orientation, where you can "just" provide a subclass which overrides the default method. Of course you will then have to re-implement the whole core method in your subclass, and figure out a way to tell the core system that it should actually use your subclass instead of the default one.
Moose allows for more fine-grained ways to override methods with it's method modifiers like before
, after
and around
. If you also add Roles to the mix (or got all in with Parametric Roles) you can build some very abstract base classes (similar to Interfaces in other languages) and leave the actual implementation as an exercise to the user...
Coincidentally, at the German Perl Workshop Ralf Schwab presented how they used AUTOLOAD
and a hierarchy of shadow classes to add a Plugin/Hook system to their Cosmo web shop (which seems to be also wildly installed and around for quite some time). (I haven't seen the talk, only the slides
I have some memories (not sure if fond or nightmarish) of a system I build between 1998 and 2004 which (ab)used the free access Perl provides to the symbol table to use some config data to dynamically generate classes, which could then later by subclassed for even more customization.
But whatever you use to implement them, the big disadvantage of Implicit Hooks is that it is rather hard to figure out when & why each piece of code is called. But to actually and properly use implicit hooks, you will also have to properly structure your code in your core classes into many small methods instead of big 100-line monsters, which also improves testabilty.
Generally, "it depends". But for Koha I think Explicit Hooks are better:
next
or SUPER
) might be a bit to much for some Plugin authors (who might be more on the librarian-who-can-code-a-bit side of the spectrum then on dev-who-happens-to-work-with-libraries)boring > magic
!Using implicit hooks could maybe make sense if Koha
around
in Moose, error handling, ...).An while it itches me in the fingers to do come up with such a smart system, I think currently dev time is better spend on other issues and improvements.
P.S.: I'm currently traveling trough Albania, so I might be slow to reply to any feedback.