Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Interfaces in Perl5 at The Perl Conference 2019...
Search
Kenta Kobayashi
June 17, 2019
Technology
0
2.9k
Interfaces in Perl5 at The Perl Conference 2019 in Pittsburgh
Kenta Kobayashi
June 17, 2019
Tweet
Share
More Decks by Kenta Kobayashi
See All by Kenta Kobayashi
Perlの生きのこり - エンジニアがこの先生きのこるためのカンファレンス2025
kfly8
1
230
Tシャツに書かれたコードを読む
kfly8
0
1.2k
Introduce Sub::Meta
kfly8
0
49
研修はイベントでなくコミュニティ作り
kfly8
0
1.2k
明日からできる新人のオンボーディングガイド
kfly8
0
790
メンター成長のためのふりかえり会
kfly8
0
1.2k
経験から効率よく学習する
kfly8
0
280
Interfaces in Perl5
kfly8
1
930
p5-Lodash!
kfly8
2
800
Other Decks in Technology
See All in Technology
エンジニアの育成を支える爆速フィードバック文化
sansantech
PRO
3
1.1k
室長と気ままに学ぶマイクロソフトのビジネスアプリケーションとビジネスプロセス
ryoheig0405
0
370
IAMポリシーのAllow/Denyについて、改めて理解する
smt7174
2
160
転生CISOサバイバル・ガイド / CISO Career Transition Survival Guide
kanny
3
1.1k
Helm , Kustomize に代わる !? 次世代 k8s パッケージマネージャー Glasskube 入門 / glasskube-entry
parupappa2929
0
270
N=1から解き明かすAWS ソリューションアーキテクトの魅力
kiiwami
0
140
【詳説】コンテンツ配信 システムの複数機能 基盤への拡張
hatena
0
130
NFV基盤のOpenStack更新 ~9世代バージョンアップへの挑戦~
vtj
0
290
JEDAI Meetup! Databricks AI/BI概要
databricksjapan
0
280
AIエージェント元年
shukob
0
120
Autonomous Database Serverless 技術詳細 / adb-s_technical_detail_jp
oracle4engineer
PRO
17
45k
ローカルLLMを活用したコード生成と、ローコード開発ツールへの応用
kazuhitoyokoi
0
140
Featured
See All Featured
The World Runs on Bad Software
bkeepers
PRO
67
11k
What's in a price? How to price your products and services
michaelherold
244
12k
How to Think Like a Performance Engineer
csswizardry
22
1.4k
The Language of Interfaces
destraynor
156
24k
Making Projects Easy
brettharned
116
6k
Adopting Sorbet at Scale
ufuk
74
9.2k
A Modern Web Designer's Workflow
chriscoyier
693
190k
Agile that works and the tools we love
rasmusluckow
328
21k
The Illustrated Children's Guide to Kubernetes
chrisshort
48
49k
How GitHub (no longer) Works
holman
314
140k
Helping Users Find Their Own Way: Creating Modern Search Experiences
danielanewman
29
2.4k
Fontdeck: Realign not Redesign
paulrobertlloyd
83
5.4k
Transcript
Interfaces in Perl5 kobaken a.k.a @kfly8 The Perl Conference 2019
#TPCiP
me • kobaken a.k.a @kfly8 • leader Gotanda.pm • orgnize
YAPC::Tokyo 2019
None
None
None
None
None
None
None
None
I ❤ Perl
Interfaces in Perl5
DBI
my $dbh = DBI->connect(...); my $items = $dbh->selectrow_arrayref(…);
Unified Interface independent of datastore
Unified Interface provides values
Limitation makes value
Agenda 1.DEMO & Features 2.Goal 3.Example: TODO app 4.Internal 5.Performance
Function::Interface is Java-like interface
DEMO
Features of Function::Interface 1.Typed interface definition 2.Check at compile time
What is Goal ?
To maintain large Perl apps
Interface is good for large apps
1. Be easier to fix implementation
2. Stable dependencies
Goal • To maintain large apps. • Interface is good
for large apps 1. Easy to fix implementation 2. Stable Dependencies
Example: TODO app
Case: “Inheritance”
package TodoRepository; use parent qw(DBI); sub new { my $class
= shift; $class->connect(…); }
package TodoRepository; … sub select { my ($self, $user_id)
= @_; $self->selectall_arrayref( ‘SELECT * FROM todos WHERE user_id = ?’, $user_id ); }
package TodoApp; use TodoRepository; my $repo = TodoRepository->new;
package TodoApp; use TodoRepository; my $repo = TodoRepository->new(…); sub my_todo_list
{ my $self = shift; my $todos = $repo->select($self->user_id); return $self->render($todos); }
TodoApp TodoRepository DBI TODO table
TodoApp TodoRepository DBI TODO table
TodoApp TodoRepository DBI TODO table Unstable Dependencies
package TodoApp; use TodoRepository; my $repo = TodoRepository->new; sub evil_method
{ $repo->do(“ANY QUERY!!!!”); }
package TodoApp; use TodoRepository; my $repo = TodoRepository->new; sub evil_method
{ $repo->do(“ANY QUERY!!!!”); } Too many features
easy to test?
my $mock = mock TodoRepository => ( select => sub
{ … } ); my $app = TodoApp->new; test $app->my_todo_list;
my $mock = mock TodoRepository => ( select => sub
{ … } ); my $app = TodoApp->new; test $app->my_todo_list; messy to test
Problems of “Inheritance” case 1.Unstable dependencies 2.Too many features 3.messy
to test
“Role” case
package TodoRepositoryInterface; use Moo::Role; requires qw(select);
package TodoRepository; use Moo; with qw( TodoRepositoryInterface ); has dbh
=> ( isa => ‘DBI::db’ );
package TodoRepository; use Moo; with qw( TodoRepositoryInterface ); has dbh
=> ( isa => ‘DBI::db’ );
package TodoRepository; … sub select { my ($self, $user_id) =
@_; $self->dbh->selectall_arrayref( ‘SELECT * FROM todos WHERE user_id = ?’, $user_id ); }
package TodoApp; use Moo; has todo_repo => ( is =>
‘ro’, does => ‘TodoRepositoryInterface’ );
package TodoApp; … sub my_todo_list { my $self = shift;
my $repo = $self->todo_repo; my $todos = $repo->select($self->user_id); return $self->render($todos); }
TodoApp TodoRepository DBI TODO table TodoRepositoryInterface
TodoApp TodoRepository DBI TODO table TodoRepositoryInterface NOT!
TodoApp TodoRepository DBI TODO table TodoRepositoryInterface more stable
Problems of “Inheritance” case 1.Unstable dependencies 2.Too many features 3.messy
to test
package TodoApp; use Moo; has todo_repo => ( is =>
‘ro’, does => ‘TodoRepositoryInterface’ ); sub evil_method { $todo_repo->do(“ANY QUERY!!!!”); }
package TodoApp; use Moo; has todo_repo => ( is =>
‘ro’, does => ‘TodoRepositoryInterface’ ); sub evil_method { $todo_repo->do(“ANY QUERY!!!!”); }
package TodoApp; use Moo; has todo_repo => ( is =>
‘ro’, does => ‘TodoRepositoryInterface’ ); sub evil_method { $todo_repo->do(“ANY QUERY!!!!”); } Necessary and sufficient features
Problems of “Inheritance” case 1.Unstable dependencies 2.Too many features 3.messy
to test
easy to test?
package TestTodoRepository; use Moo; with qw( TodoRepositoryInterface ); sub select
{ … }
package TestTodoRepository; use Moo; with qw( TodoRepositoryInterface ); sub select
{ … } Be easier to test
Problems of “Inheritance” case 1.Unstable dependencies 2.Too many features 3.messy
to test
no problem at all?
package TodoRepositoryInterface; use Moo::Role; requires qw(select); sub surprised_method { ..
do anything }
package TodoRepositoryInterface; use Moo::Role; requires qw(select); sub surprised_method { ..
do anything } Implementation reusable
package TodoRepositoryInterface; use Moo::Role; requires qw(select);
select($id) ? select(id => $id) ? select({ id => $id
}) ?
select($id) # => arrayref of Todo ? # => iterator
of Todo ?
select($id) # => arrayref of Todo ? # => iterator
of Todo ? Ambiguous interface input / output
Problems of “Role” case 1.Implementation reusable 2.Ambiguous interface input /
output
“Function::Interface” case
package TodoRepositoryInterface; use Function::Interface; use TodoTypes; method select(UserID $user_id) :Return(ArrayRef[Todo]);
Problems of “Role” case 1.Implementation reusable 2.Ambiguous interface input /
output
package TodoRepositoryInterface; use Function::Interface; use TodoTypes; method select(UserID $user_id) :Return(ArrayRef[Todo]);
sub surprising_method { … do anything }
package TodoRepositoryInterface; use Function::Interface; use TodoTypes; method select(UserID $user_id) :Return(ArrayRef[Todo]);
sub surprising_method { … do anything }
Problems of “Role” case 1.Implementation reusable 2.Ambiguous interface input /
output
package TodoRepository; use TodoTypes; use Function::Interface::Impl qw( TodoRepositoryInterface ); has
dbh => ( … ); method select(UserID $user_id) :Return(ArrayRef[Todo]) { … }
package TodoApp; use Moo; use TodoTypes; has todo_repo => (
isa => ImplOf["TodoRepositoryInterface"], ); sub my_todo_list { … }
Looks Good!
Internal
requirements 1.function implementation 2.function interface 3.check if interface is implmented
4.interface type
1. function implementation
Function::Parameters • subroutine signatures • developed by MAUKE
use Function::Parameters; use Types::Standard -types; fun add(Int $a, Int $b)
{ return $a + $b }
my $info = Function::Parameters::info(\&add); $info->positional_required; # => Int $a, Int
$b
Function::Return • specify function return types • created by myself
sub add :Return(Int) { 3.14 } add(); # ERROR! Invalid
type
my $info = Function::Return::info(\&add); $info->types; # => Int
Appendix about Function::Return
sub multi :Return(Num, Str) { 3.14, ‘message' } my ($pi,
$msg) = multi();
sub multi :Return(Num, Str) { 3.14, ‘message' } my ($pi,
$msg) = multi(); my $count = multi(); # ERROR!
requirements 1.function implementation 2.function interface 3.check if interface is implemented
4.interface type
2. function interface
Function::Interface • Keyword::Simple • PPR
Deparse fun hello() :Return(Str);
sub BEGIN { Function::Interface::_register_info({ package => ‘HelloInterface', keyword => ‘fun',
subname => ‘message', params => [], return => [&Str()]} ); }
my $info = Function::Interface::info(“HelloInterface”); $info->functions; # => hello(Str $msg) :Return(Str)
requirements 1.function implementation 2.function interface 3.check if interface is implemented
4.interface type
3.check if interface is implemented
use Function::Interface::Impl qw( FooInterface BarInterface BazInterface );
F::Parameters#info F::Return#info F::Interface#info
F::Parameters#info F::Return#info F::Interface#info
requirements 1.function implementation 2.function interface 3.check if interface is implemented
4.interface type
use Function::Interface::Types; my $type = ImplOF[‘FooInterface’]; # Foo is implements
of FooInterface my $foo = Foo->new; $type->check($foo);
requirements 1.function implementation 2.function interface 3.check if interface is implemented
4.interface type
Performance
F::I::Impl runs at compile time
F::Return has `no_check` option
Let’s benchmark
F::P + F::R + F::I F::P + F::R no_check +
F::I F::P + F::R no_check F::P Case1 Case4 Case2 Case3
F::P + F::R + F::I F::P + F::R no_check +
F::I F::P + F::R no_check F::P 360653.77/s 1499189.22/s 1499189.22/s 1499189.22/s Case1 Case4 Case2 Case3
$BTF $BTF $BTF $BTF
Conclusion
Features of F::Interface 1.Typed interface definition 2.Check at compile time
Goal • To maintain large apps. • Interface is good
for large apps 1. Easy to fix implementation 2. Stable Dependencies
Internal • function implementation • Function::Parameters + Function:\:Return • function
interface • Keyword::Simple + PPR • compare meta infos at compile time
Performance • The same speed as using only F::Parameters •
Function::Interface::Impl runs at CHECK phase • Function::Return has `no_check` option
Questions?
Thank you!