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
Snake Snacks: Function Composition, The Dumb Way
Search
Brian Hicks
September 07, 2017
Technology
0
130
Snake Snacks: Function Composition, The Dumb Way
Brian Hicks
September 07, 2017
Tweet
Share
More Decks by Brian Hicks
See All by Brian Hicks
Esperanto
brianhicks
0
130
Make Snacks: Yet Another JavaScript Build System
brianhicks
0
98
State of Elm 2017
brianhicks
1
530
µKanren: A Minimal Functional Core for Relational Programming
brianhicks
0
430
Terraform All The Things!
brianhicks
2
390
Kubernetes for the Mesos User
brianhicks
1
99
ch-ch-ch-ch-changes in Elm 0.17.0
brianhicks
2
1.8k
State of Elm 2016
brianhicks
3
540
Mesos + Consul = Developer Happiness (JUG)
brianhicks
1
130
Other Decks in Technology
See All in Technology
機械学習を扱うプラットフォーム開発と運用事例
lycorptech_jp
PRO
0
250
AI時代を生き抜くエンジニアキャリアの築き方 (AI-Native 時代、エンジニアという道は 「最大の挑戦の場」となる) / Building an Engineering Career to Thrive in the Age of AI (In the AI-Native Era, the Path of Engineering Becomes the Ultimate Arena of Challenge)
jeongjaesoon
0
110
なぜスクラムはこうなったのか?歴史が教えてくれたこと/Shall we explore the roots of Scrum
sanogemaru
5
1.6k
開発者を支える Internal Developer Portal のイマとコレカラ / To-day and To-morrow of Internal Developer Portals: Supporting Developers
aoto
PRO
1
460
複数サービスを支えるマルチテナント型Batch MLプラットフォーム
lycorptech_jp
PRO
1
370
RSCの時代にReactとフレームワークの境界を探る
uhyo
10
3.4k
20250910_障害注入から効率的復旧へ_カオスエンジニアリング_生成AIで考えるAWS障害対応.pdf
sh_fk2
3
260
LLMを搭載したプロダクトの品質保証の模索と学び
qa
0
1.1k
企業の生成AIガバナンスにおけるエージェントとセキュリティ
lycorptech_jp
PRO
2
170
Snowflake Intelligenceにはこうやって立ち向かう!クラシルが考えるAI Readyなデータ基盤と活用のためのDataOps
gappy50
0
230
大「個人開発サービス」時代に僕たちはどう生きるか
sotarok
20
10k
2025年になってもまだMySQLが好き
yoku0825
8
4.8k
Featured
See All Featured
Docker and Python
trallard
45
3.6k
[RailsConf 2023] Rails as a piece of cake
palkan
57
5.8k
Mobile First: as difficult as doing things right
swwweet
224
9.9k
Code Review Best Practice
trishagee
70
19k
YesSQL, Process and Tooling at Scale
rocio
173
14k
[Rails World 2023 - Day 1 Closing Keynote] - The Magic of Rails
eileencodes
36
2.5k
Learning to Love Humans: Emotional Interface Design
aarron
273
40k
Fantastic passwords and where to find them - at NoRuKo
philnash
52
3.4k
Producing Creativity
orderedlist
PRO
347
40k
Making Projects Easy
brettharned
117
6.4k
Speed Design
sergeychernyshev
32
1.1k
Sharpening the Axe: The Primacy of Toolmaking
bcantrill
44
2.5k
Transcript
Snake Snacks FUNCTION COMPOSITION, THE DUMB WAY
WHAT WE WANT def inc(n): return n + 1 def
double(n): return n * 2 # in the REPL >>> (inc >> double)(2) 6 >>> (double >> inc)(2) 5
HOW ARE WE GONNA GET THERE? The Worst Way Possible™
DOUBLE UNDERSCORE METHODS
DOUBLE UNDERSCORE METHODS
DUNDER METHODS
DUNDER MIFFLIN
DUNDER METHODS, THE NICE WAY class Boss(object): def __init__(self, name):
self.name = name def __str__(self): return self.name def __repr__(self): return '<%s: %s>' % (self.__class__.__name__, self) def introduce(self): return "Please meet my boss, %s" % self
DUNDER METHODS, THE NICE WAY >>> b = Boss("Michael Scott")
>>> b <Boss: Michael Scott> >>> str(b) 'Michael Scott' >>> b.introduce() 'Please meet my boss, Michael Scott'
! DECORATORS "
DECORATORS, THE NICE WAY def memoize(fn): cache = {} def
inner(*args, **kwargs): key = str((args, kwargs)) if key not in cache: cache[key] = fn(*args, **kwargs) return cache[key] return inner
DECORATORS, THE NICE WAY @memoize def hype(stuff): return "OH YEAH,
IT'S %s" % stuff.upper() # is the same as... hype = memoize(lambda stuff: "OH YEAH, IT'S %s" % stuff.upper())
DECORATORS, THE NICE WAY >>> hype("cheese") "OH YEAH, IT'S CHEESE"
>>> hype("a moose") "OH YEAH, IT'S A MOOSE"
BUT… OBJECTS! class memoize(object): def __init__(self, fn): self.cache = {}
self.fn = fn def __call__(self, *args, **kwargs): key = str((args, kwargs)) if key not in self.cache: self.cache[key] = self.fn(*args, **kwargs) return self.cache[key]
BUT… OBJECTS! >>> hype("cheese") "OH YEAH, IT'S CHEESE" >>> hype("a
moose") "OH YEAH, IT'S A MOOSE" >>> hype.cache {"(('a moose',), {})": "OH YEAH, IT'S A MOOSE", "(('cheese',), {})": "OH YEAH, IT'S CHEESE"}
__gt__ class ChessPlayer(object): def __init__(self, name, elo): self.name = name
self.elo = elo def __gt__(self, other): return self.elo > other.elo
__gt__ >>> carlsen = ChessPlayer("Carlsen, Magnus", 2827) >>> almasi =
ChessPlayer("Almasi, Zoltan", 2707) >>> carlsen > almasi True >>> carlsen < almasi False
OUR FIRST TRY! class composable(object): def __init__(self, fn): self.fn =
fn def __call__(self, *args, **kwargs): return self.fn(*args, **kwargs) def __gt__(self, other): return self.__class__( lambda *args, **kwargs: other(self.fn(*args, **kwargs)) )
OUR FIRST TRY! @composable def inc(n): return n + 1
@composable def double(n): return n * 2 @composable def triple(n): return n * 3
OUR FIRST TRY! >>> (inc > inc)(0) 2 >>> (inc
> inc > inc)(0) 2
OUR FIRST TRY! ! 1 > 2 > 3 #
is equivalent to 1 > 2 and 2 > 3 # NOT (1 > 2) > 3
__rshift__ TO THE RESCUE! class composable(object): def __init__(self, fn): self.fn
= fn def __call__(self, *args, **kwargs): return self.fn(*args, **kwargs) def __rshift__(self, other): return self.__class__( lambda *args, **kwargs: other(self.fn(*args, **kwargs)) )
__rshift__ TO THE RESCUE! >>> (inc >> inc)(0) 2 >>>
(inc >> inc >> inc)(0) 3
__rshift__ TO THE RESCUE! >>> (inc >> double)(2) 6 >>>
(double >> inc)(2) 5 >>> (inc >> double >> triple)(2) 18
THANK YOU I'M SORRY