Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Speaker Deck
PRO
Sign in
Sign up for free
Generative Programming in Go
monochromegane
June 21, 2015
Technology
16
6.8k
Generative Programming in Go
GoCon2015発表資料
https://github.com/GoCon/GoCon/blob/master/2015summer.rst
monochromegane
June 21, 2015
Tweet
Share
More Decks by monochromegane
See All by monochromegane
再帰化への認知的転回/the-turn-to-recursive-system
monochromegane
0
120
仮想的な探索を用いて文脈や時間の経過による番狂わせにも迅速に追従する多腕バンディット手法/wi2_lkf_bandits
monochromegane
0
140
Synapse: 文脈と時間経過に応じて推薦手法の選択を最適化するメタ推薦システム/smash21-synapse
monochromegane
0
110
なめらかなシステムと運用維持の未来/dicomo2021-coherently-fittable-system
monochromegane
1
4.1k
go:embedでExplainable Binaryを作る/fukoukago17_go_code_embedding
monochromegane
2
120
非定常な多腕バンディット問題において効率的に変化を察知する方式の検討/wsa8_predictive_exploratory_model
monochromegane
0
1.6k
変化検出と要約データ構造を用いた利用者の嗜好の変化に迅速に追従する多腕バンディット手法/iots2020-adaptive-linear-mab
monochromegane
0
490
嗜好伝達コミュニケーションの効率化を目指した伝達方式の検討/wsa7_local_preference
monochromegane
0
2.1k
なめらかなシステムの実現に向けて/coherently-fittable-system
monochromegane
0
250
Other Decks in Technology
See All in Technology
220428event_overview
caddi_eng
1
200
株式会社オプティム_採用会社紹介資料 / optim-recruit
optim
0
5.2k
ここらでGPSマルチユニットが如何に使いやすいか本気で説明するから聞きなさい
mitsuzono
0
310
Research Paper Introduction #98 "NSDI 2022 recap"
cafenero_777
0
180
Okta Identity Engineってどうよ?
tatsumin39
0
280
Devに力を授けたいSREのあゆみ / SRE that wants to empower developers
tocyuki
3
410
JAWS-UG 朝会 #33 登壇資料
takakuni
0
350
Kubernetesの上に作る、統一されたマイクロサービス運用体験
tkuchiki
1
660
~スタートアップの人たちに捧ぐ~ 監視再入門 in AWS
track3jyo
PRO
30
8.2k
【OCHaCafe#5】その Pod 突然落ちても大丈夫ですか?
k6s4i53rx
2
110
OSINT/GEOINT ワークショップ 20220514 古橋資料
furuhashilab
2
220
失敗しない条件付きアクセス Season 3
sophiakunii
0
1.1k
Featured
See All Featured
How to train your dragon (web standard)
notwaldorf
57
3.8k
Rebuilding a faster, lazier Slack
samanthasiow
62
7.2k
No one is an island. Learnings from fostering a developers community.
thoeni
9
1.1k
The World Runs on Bad Software
bkeepers
PRO
56
5.2k
Code Review Best Practice
trishagee
41
6.7k
How to name files
jennybc
39
58k
Making Projects Easy
brettharned
98
4.3k
Bootstrapping a Software Product
garrettdimon
294
110k
Optimizing for Happiness
mojombo
365
63k
Three Pipe Problems
jasonvnalue
89
8.6k
BBQ
matthewcrist
74
7.9k
Stop Working from a Prison Cell
hatefulcrawdad
261
17k
Transcript
Generative Programming in Go - GoCon 2015 summer - @monochromegane
MIYAKE Yusuke (@monochromegane)
GMO Pepabo, Inc.
♕ 3 GitHub Awards Go ranking in Japan :)
Generative Programming
ੜతͳ Programming
Generator + Template parse generate Parser Your App Generated Code
AST Code use
Attention, please.
✘ Generics Meta programming Dynamic generation
parse Parser AST Code Go provides
Generator + Template generate Your App Generated Code use We
implement
argen ActiveRecord Generator
GoͰDataMapperͰͳ͘ ActiveRecordϥΠΫʹ DBૢ࡞͢Δ
by Generative programming
ߏମʹ`+AR`ϚʔΧʔΛ͚ͭΔ //+AR type User struct { Id int Name string
Age int }
ੜ͢Δ $ argen main.go $ tree . !"" main.go #""
main_gen.go
ߏମʹARϥΠΫͳϝιου͕ Ճ͞ΕΔ db, _ := sql.Open("sqlite3", "foo.db") Use(db) u :=
User{Name: "test", Age: 20} u.Save() //// INSERT INTO users (name, age) VALUES (?, ?); [test 20] User{}.Where("name", "test").And("age", ">", 20).Query() //// SELECT users.id, users.name, users.age FROM users WHERE name = ? AND age > ?; [test 20]
Generative Programming ͍υίϩ
Case.1 Generics
ҙͷߏମʹڞ௨ͷϝιου Λ࣋ͨͤͭͭɺݸʑͷܕΛѻ͏ var u User u = User{}.First() var h
Hoge h = Hoge{}.First()
ҙͷߏମʹڞ௨ͷϝιου Λ࣋ͨͤͭͭɺݸʑͷܕΛѻ͏ var u User u = User{}.First() var h
Hoge h = Hoge{}.First() • Ωϟετͨ͘͠ͳ͍ • Genericsͷग़൪
ᵆᴸᴸᴸᴸᴸᴸᴸᴸᴸᴸᴸᴸᴸᵪᴸᴸᵊ ᴺwhy no generics golangɹ ᴺݕࡧᴺ ᵎᴸᴸᴸᴸᴸᴸᴸᴸᴸᴸᴸᴸᴸᵲᴸᴸᵒ
Let’s generate !
ߏମʹରͯ͠ݸʑͷܕΛѻ͏ ڞ௨ͷϝιουΛੜ
func (m User) First() (*User, error) { return m.newRelation().First() }
func (r *UserRelation) First() (*User, error) { return r.Order("id", "ASC").Limit(1).QueryRow() } func (r *UserRelation) QueryRow() (*User, error) { row := &User{} err := r.Relation.QueryRow( row.fieldPtrsByName( r.Relation.GetColumns())...) if err != nil { return nil, err } return row, nil }
see also: clipperhouse/gen // +gen slice:"All" type Person struct {
Name string Present bool } gang := PersonSlice { {"Alice", true}, {"Bob", false}, {"Carly", true}, } here := func(p Person) bool { return p.Present } gang.All(here) // => false, Bob didn't make it
Case.2 Performance
ϦϑϨΫγϣϯΛͬͨ൚༻ੑ ύϑΥʔϚϯεͱҾ͖͑ // Useful! but... var u User db.First(&u)
ϕϯνϚʔΫ // read SomeFunc(s.F) SomeFunc(reflect.ValueOf(s).FieldByName("F").Int()) // write s.F = 100
reflect.ValueOf(&s).Elem().FieldByName("F").SetInt(100) $ go test -benchmem -bench . • Mac OSX(10.10.3) • CPU: 2.5GHz Core i5(2Core) • Memory: 8GB • Go: 1.4.2
ߏମϑΟʔϧυʹର͢ΔΞΫηε time Alloced Bytes Allocs read field 0.38 ns 0
B 0 allocs reflect 246 ns 16 B 2 allocs write field 0.36 ns 0 B 0 allocs reflect 199 ns 8 B 1 allocs
ෳͷߏମϑΟʔϧυʹର͢ΔΞΫηε time Alloced Bytes Allocs read field 0.36 ns 0
B 0 allocs reflect 583 ns 88 B 2 allocs write field 0.37 ns 0 B 0 allocs reflect 277 ns 8 B 1 allocs
Let’s generate !
ߏମʹରͯ͠ϑΟʔϧυใ औಘ༻ϝιουΛੜ
func (m *User) fieldValueByName(name string) interface{} { switch name {
case "id", "users.id": return m.Id case "name", "users.name": return m.Name case "age", "users.age": return m.Age default: return "" } } func (m *User) fieldPtrByName(name string) interface{} { switch name { case "id", "users.id": return &m.Id case "name", "users.name": return &m.Name case "age", "users.age": return &m.Age default: return nil } }
see also: pquerna/ffjson //go:generate ffjson $GOFILE type Foo struct {
Bar string } f := Foo{"bar"} b, _ := json.Marshal(f) fmt.Printf("%s\n", string(b)) // => {"Bar":"bar"} https://github.com/pquerna/ffjson
Case.3 DSL
ҙͷߏମͷڞ௨ϝιου هड़༰͕ʹͳΓ͕ͪ // far from the DSL... func (u *User)
BeforeUpdate() (err error) { if u.Name != "abc"{ return fmt.Errorf("%s is invalid name.", u.Name) } if u.Age > 20 { return fmt.Errorf("%d is invalid age.", u.Age) } return nil }
Let’s generate !
ϝιου໊/ίϝϯτ/λά͔Β ఆٛΛิͯ͠ੜ
func (u User) validatesName() ar.Rule { return ar.MakeRule().Format().With("abc").OnCreate() } func
(u User) validatesAge() ar.Rule { return ar.MakeRule().Numericality().OnlyInteger().LessThan(20) } rules := map[string]*ar.Validation{ "name": m.validatesName().Rule(), "age": m.validatesAge().Rule(), } for name, rule := range rules { if ok, errs := ar.NewValidator(rule).On(on).IsValid(m.fieldValueByName(name)); !ok { result = false errors.SetErrors(name, errs) } } >
Case. Bad
ͳΜͰGenerate
• ϝιουͷڞ௨Խɺଟଶੑͷ࣮ݱͳͲߏମͷຒࠐ (ҕৡ)interfaceΛͬͯΔ͖ • http://go-talks.appspot.com/github.com/lestrrat/ go-slides/2014-yapcasia-go-for-perl-mongers/ main.slide#27 • http://blog.monochromegane.com/blog/ 2014/03/23/struct-implementaion-patterns-in-
golang/ • Generate࣮ଆར༻ଆҰख͔͔ؒΔɺෳࡶ ʹͳΓ͕ͪɻGenerateͰΔཧ༝͕આ໌Ͱ͖ͳ͍ͷ Ͱ͋Ε͏͖Ͱͳ͍
Tips
ίϚϯυϥΠϯ/go generate ͷ྆ํʹରԠ͢Δ
from := os.Getenv("GOFILE") if from == "" { if len(args)
> 0 { from = args[0] } else { os.Exit(1) } } $ argen main.go // go:generate argen
defineΛͬͯ templateΛׂཧ͢Δ
{{template "Relation" .}} {{define "Relation"}} type {{.Name}}Relation struct { src
*{{.Name}} *ar.Relation } {{end}} func (t Template) toDefine() string { return fmt.Sprintf("{{define \"%s\"}}%s{{end}}\n", t.Name, t.Text) } var relation = &Template{ Name: "Relation", Text: ` type {{.Name}}Relation struct { src *{{.Name}} *ar.Relation }`
templateͰ ࣗಈܗͱ ΦʔτΠϯϙʔτ
func writeWithFormat(file, template string, structs structs) ([]byte, error) { var
b bytes.Buffer w := bufio.NewWriter(&b) write(w, template, structs) w.Flush() formatted, err := imports.Process(file, b.Bytes(), nil) if err != nil { return nil, err } return formatted, nil } func write(w io.Writer, tplText string, structs structs) error { t := template.New("t") t.Funcs(template.FuncMap{}) tpl := template.Must(t.Parse(tplText)) if err := tpl.Execute(w, structs); err != nil { return err } return nil }
ςετੜʹ ରͯ͠ߦ͏
//go:generate go run ../cmd/argen/main.go package tests import "github.com/monochromegane/argen" //+AR type
User struct { Name string Age int } $ go generate && go test ./...
એ ϖύϘͰΤϯδχΞΛืू͍ͯ͠·͢ɻ ڞʹαʔϏεΛੜΈग़͠ҭͯͯ͘ΕΔ৽͍ؒ͠ Λ͍ͬͯ·͢ɻ http://pepabo.com/recruit/career/engineer/
͓ΘΓ