今あらためて読み直したい Go 基礎知識その2 / golang.tokyo #25

©2019 Wantedly, Inc. ࠓ͋ΒͨΊͯಡΈ௚͍ͨ͠ Goجૅ৘ใͦͷ golang.tokyo #25 Jun 18, 2019
- @izumin5210

©2019 Wantedly, Inc. @izumin5210 Application Engineer, Wantedly People Wantedly, Inc.
‣ ͓΋ʹ#BDLFOE&OHJOFFSΛ͍ͯ͠·͢ ‣ (Pͱ3VCZͱɺ·Εʹ8FCϑϩϯτΤϯυ ‣ ࠷ۙͷ͓͖ʹ͍Γ͸HPMBOHPSHYUPPMTHPQBDLBHFTQBDLBHFTUFTU

©2019 Wantedly, Inc. Go Data Structures: Interfaces Go's interfaces—static, checked
at compile time, dynamic when asked for— are, for me, the most exciting part of Go from a language design point of view. If I could export one feature of Go into other languages, it would be interfaces. Page Title Page Subtitle https://research.swtch.com/interfaces

©2019 Wantedly, Inc. Go Data Structures: Interfaces https://research.swtch.com/interfaces ‣ 3VTT$PY
!STD ʹΑΔJOUFSGBDFͷղઆʢʣ (Pͷൃද͕Β͍͠ ‣ લ൒ͰJOUFSGBDFͷ࢖͍ํͷղઆ FH ίϯύΠϧ࣌ܕνΣοΫͭͭ͠%VDL5ZQJOHͰ͖Δʂ EZOBNJDͰ΋ܕνΣοΫͰ͖Δʂʢ5ZQFTXJUDIFTʣ ೥લͷهࣄ͚ͩͲࠓݟͯ΋ҧ࿨ײͳ͍ ‣ ޙ൒͸JOUFSGBDFͷσʔλߏ଄΍࣮૷ʹ͍ͭͯ ࢓༷ɾػೳղઆ Go Data Structures: Interfaces

©2019 Wantedly, Inc. Interfaceͷσʔλߏ଄ ‣ *OUFSGBDF͕ͲͷΑ͏ʹ࣮ͯ͠ݱ͞Ε͍ͯΔ͔ IUUQTHJUIVCDPNHPMBOHHPCMPCHPͱ͔΍Δͱ  งғؾ͍ۙίʔυ͕ग़ͯ͘Δ ‣
σʔλߏ଄ ӈਤΈ͍ͨͳ࿩ ͋ΘͤͯಡΈ͍ͨ(P%BUB4USVDUVSFT ࠓͩͱTSDSVOUJNF\JGBDF SVOUJNF^HP͋ͨΓ ‣ ಺෦࣮૷ʢ௥͍͖Εͣʜʣ ࢓༷ɾػೳղઆ Go Data Structures: Interfaces * https://research.swtch.com/godata

©2019 Wantedly, Inc. Go Slices: usage and internals https://blog.golang.org/go-slices-usage-and-internals ‣
"OESFX(FSSBOE BEH ʹΑΔTMJDFͷղઆʢʣ ͜ͷ࣌఺Ͱ͸·ͩ(P͸ʹͳ͍ͬͯͳ͍ ‣ લ൒Ͱ"SSBZ͓Αͼ4MJDFͷ࢖͍ํͷղઆ FHॳظԽ NBLF MFO DBQ ΞΫηεͷ࢓ํ ঺հ͞ΕͯΔίʔυશ෦ࠓͰ΋ಈ͘ ‣ ޙ൒͸TMJDFͷσʔλߏ଄ʹ͍ͭͯ ࢓༷ɾػೳղઆ Go Slices: usage and internals

©2019 Wantedly, Inc. Sliceͷσʔλߏ଄ɾ࣮૷ ‣ 4MJDFͷσʔλߏ଄ͷ࿩ ಺෦తʹ͸BSSBZ΁ͷQPJOUFS MFO DBQΛ΋͍ͬͯΔ
ʜΈ͍ͨͳ࿩ ‣ CVJMUJOؔ਺ͷߟ͑ํ ʮTMJDFͷDBQΛ૿΍͢ʯʹ͸ɺഒͷDBQΛ࣋ͭ  TMJDFΛ࡞Γ௚ͤ͹͍͍ΑͶDPQZ ʮTMJDF΁ͷ஋௥Ճʯʹ͸ɺద੾ʹDBQ૿΍ͭͭ͠  ຤ඌʹDPQZ͢Ε͹͍͍ΑͶBQQFOE ࢓༷ɾػೳղઆ s = s[2:4] s = s[:cap(s)] Go Slices: usage and internals

©2019 Wantedly, Inc. Arrays, slices (and strings): The mechanics of
'append' https://blog.golang.org/slices ‣ 3PC1JLFʹΑΔTMJDF·ΘΓͷղઆʢʣ (PϦϦʔε͔Β೥ޙ͘Β͍ ‣ ʮॳֶऀ͕ʢଞͷݴޠ͔Βͷઌೖ؍Ͱʁʣ4MJDFͭ·͖͕ͣͪʯ  ͳͷͰɺBQQFOEͷڍಈ͔Βඥղ͍͍ͯ͘ ‣ "SSBZ 4MJDFͷղઆΛͯ͠ɺ4MJDFʹ͍ͭͯ۷ΓԼ͍͛ͯ͘ "TMJDFJTOPUBOBSSBZ"TMJDFEFTDSJCFTBQJFDFPGBOBSSBZ ࢓༷ɾػೳղઆ Arrays, slice (and strings): The mechanics of 'append'

©2019 Wantedly, Inc. Slice ͷৼΔ෣͍͔ΒڍಈΛཧղ͢Δ ‣ 4MJDFͷ಺෦ߏ଄Λཧղ͢Δ 4MJDFT5IFTMJDFIFBEFS
ؔ਺ͷҾ਺΍ϨγʔόʹεϥΠεΛೖΕͯΈͯɺ಺෦ߏ଄ͷཧղͷॿ͚ʹ ‣ (P4MJDFTVTBHFBOEJOUFSOBMTʹ͋ͬͨΑ͏ͳྲྀΕ 4MJDFʹ͸࣮͸DBQ͕͋Δ େ͖͍4MJDFΛ࡞ΔͨΊʹNBLF͕͋Δ 4MJDFΛFYUFOE͢Δେ͖͍4MJDFʹDPQZ͢Δ ͜ΕΒΛ૊Έ߹ΘͤͯBQQFOEΛ࣮ݱ͢Δ ‣ ͋ͱ͸OJMTMJDF΍TUSJOHͷ࿩ ࢓༷ɾػೳղઆ Arrays, slice (and strings): The mechanics of 'append' // Append appends the elements to the slice. // Efficient version. func Append(slice []int, elements ...int) []int { n := len(slice) total := len(slice) + len(elements) if total > cap(slice) { // Reallocate. Grow to 1.5 times the new size, newSize := total*3/2 + 1 newSlice := make([]int, total, newSize) copy(newSlice, slice) slice = newSlice } slice = slice[:total] copy(slice[n:], elements) return slice } Snippet from https://blog.golang.org/slices

©2019 Wantedly, Inc. Constants https://blog.golang.org/constants ‣ 3PC1JLFʹΑΔDPOTUͷղઆʢʣ (PϦϦʔεͷϲ݄ޙ͘Β͍ ‣
ม਺ͱ͸ҧ͏ɺzී௨ͷ਺ࣈzͬΆ͘ৼΔ෣͏ఆ਺ʹ͍ͭͯ qPBU JOU͸μϝɺJOU JOU΋μϝ Ͱ΋A1e6 * time.SecondA͸ڐ͞ΕΔ ‣ $Ͱ͸͍ΖΜͳʮ਺஋ʯΛࠞͥΒΕΔ͕ɺCVHʹ΋ʜ  (PͰ͸ېࢭʹ͍ͨ͠ɺ͚ͲAJOU AΈ͍ͨͳͷ͸ΊΜͲ͍ʜ ࢓༷ɾػೳղઆ Constants

©2019 Wantedly, Inc. Constants ‣ ADPOTUIFMMP)FMMP ੈքAͷ࣌఺Ͱ͸·ͩTUSJOHͰ͸ͳ͍ 6OUZQFETUSJOHDPOTUBOUͰ͋Δ
ʢDPOTUBOUUFYUVBMWBMVFͱ΋දݱ͍ͯͨ͠ʣ ‣ ͜ͷ͋ͱ%FGBVMUUZQF͔Βܕͷܾఆͷ࿩ʹҠ͍ͬͯ͘ ‣ ͍࣍ͰTUSJOHҎ֎ͷܕCPPMFBO qPBU ͱଓ͘ ‣ ࠷ޙʹ਺஋ɺ*OUFHFS qPBU DPNQMFYͱ͢΂ͯΛ಺แ͢Δ࿩ ࢓༷ɾػೳղઆ Constants

©2019 Wantedly, Inc. The Go Memory Model https://golang.org/ref/mem ‣ (PͷϝϞϦϞσϧͷղઆʢʣ
͋ΔHPSPVUJOFͰॻ͖ࠐΈ͕͋ͬͨม਺Λ  ผͷHPSPVUJOFͰಡΈऔΔ͜ͱ͕Ͱ͖Δ͜ͱʹ͍ͭͯ ࢓༷ɾػೳղઆ The Go Memory Model *GZPVNVTUSFBEUIFSFTUPGUIJTEPDVNFOUUPVOEFSTUBOE UIFCFIBWJPSPGZPVSQSPHSBN ZPVBSFCFJOHUPPDMFWFS    %POUCFDMFWFS

©2019 Wantedly, Inc. Happens before ‣ ·ͣ)BQQFOTCFGPSFͱ͍͏ؔ܎Λఆ͍ٛͯ͠Δ FHಡΈࠐΈॲཧS͕W΁ͷॻ͖ࠐΈॲཧXΛ؍ଌ͢Δʹ͸  SEPFTOPUIBQQFOTCFGPSFXͰͳ͍ͱ͍͚ͳ͍
ԿΛอূ͢Δ͜ͱͰσʔλڞ༗Λ࣮ݱ͍ͯ͠Δ͔Λղઆ͢Δ ‣ ӈͷྫʢDIBOOFMʣͰ͋Ε͹ 5IFXSJUFUPBIBQQFOTCFGPSFUIFTFOEPOD 5IFTFOEPODIBQQFOTCFGPSFUIFSFDFJWFPOD 5IFSFDFJWFPODIBQQFOTCFGPSFUIFQSJOU ࢓༷ɾػೳղઆ Go Slices: usage and internals var c = make(chan int, 10) var a string func f() { a = "hello, world" c <- 0 } func main() { go f() <-c print(a) }

©2019 Wantedly, Inc. Buffered chan, Lock, Once ‣ #V⒎FSSFE$IBOOFMͷৼΔ෣͍΍ͦΕΛԠ༻ͨ͠  ಉ࣮࣌ߦ਺੍ݶ͖ͭXPSLFS΍ɺ 
-PDL΍0ODF͕ʮͳʹΛอূͯ͘͠ΕΔ͔ʯͷ  ղઆ͕͋Δ ‣ ϖʔδ಺ΛCFGPSF΍HVBSBOUFFͰHSFQ͢ΔͱಡΈ΍͍͢ ࢓༷ɾػೳղઆ Go Slices: usage and internals var l sync.Mutex var a string func f() { a = "hello, world" l.Unlock() } func main() { l.Lock() go f() l.Lock() print(a) } var a string var once sync.Once func setup() { a = "hello, world" } func doprint() { once.Do(setup) print(a) } func twoprint() { go doprint() go doprint() } Lock Once

©2019 Wantedly, Inc. Diagnostics https://golang.org/doc/diagnostics.html ‣ (PΤίγεςϜ͕ఏڙ͢Δ  UPPMTUPEJBHOPTFMPHJDBOEQFSGPSNBODFQSPCMFNT·ͱΊ ΧςΰϦʹ෼ྨͯ͠ղઆ͢Δ
1SPpMJOH 5SBDJOH %FCVHHJOH 3VOUJNFTUBUJTUJDTBOEFWFOUT ࢓༷ɾػೳղઆ Diagnostics

©2019 Wantedly, Inc. Profiling net/http/pprof & runtime/pprof ‣ ʮॏ͍ͨίʔυʯʮେྔʹݺ͹ΕΔίʔυʯΛ୳͢ॿ͚ʹͳΔ
औΕΔσʔλʢGSPNIUUQTHPMBOHPSHQLHSVOUJNFQQSPG1SPpMFʣ - goroutine - stack traces of all current goroutines - heap - a sampling of memory allocations of live objects - allocs - a sampling of all past memory allocations - threadcreate - stack traces that led to the creation of new OS threads - block - stack traces that led to blocking on synchronization primitives - mutex - stack traces of holders of contended mutexes ‣ 1SPEVDUJPOTBGF͚ͩͲɺଟগ͸σάϨ͢ΔΑɻNVMUJSFQMJDBͷ͏ͪͷQSPDFTT͚ͩʹ͠Α͏Ͷɻ ʜΈ͍ͨͳ࢖͍ํͷίπΈ͍ͨͳͷ΋ॻ͍ͯ͋Δ ࢓༷ɾػೳղઆ Diagnostics

©2019 Wantedly, Inc. Tracing golang.org/x/net/trace, net/http/httptrace, ... ‣ ʮ͔͜͜Β͜͜·ͰͰԿNT͔͔ͬͨʯΈ͍ͨͳܭଌ
ΞϓϦʹด͡Δ΋ͷ΍ɺෳ਺ΞϓϦʹ·͕ͨΔ΋ͷͳͲʢ෼ࢄτϨʔγϯάʣ USBDFPCKFDU͸DPOUFYU$POUFYUʹ͍Εͯ఻ൖͤ͞Α͏ʂΈ͍ͨͳϓϥΫςΟε΋ॻ͍ͯ͋Δ ࢓༷ɾػೳղઆ Diagnostics

©2019 Wantedly, Inc. Debugging Delve, GDB and core dump!! ‣
ίʔυதʹϒϨʔΫϙΠϯτΛஔ͍ͯɺ  ͕࣮ͦ͜ߦ͞ΕΔλΠϛϯάͷม਺ΛΈͨΓؔ਺Λεςοϓ࣮ߦͨ͠ΓʜΈ͍ͨͳΞϨ ‣ AHPCVJMEAʹϑϥάΛ଍͢͜ͱͰ࠷దԽΛݮΒ͠ɺσόοά͠΍͘͢Ͱ͖ΔΑΈ͍ͨͳ࿩͕͋Δ ‣ A(053"$&#"$,DSBTIAʹͯ͠ϓϩάϥϜΛ࣮ߦ͠ɺ4*("#35Λ౤͛ΔͱDPSFEVNQు͔ͤΔ͜ͱ΋  Ͱ͖ΔΒ͍͠ ࢓༷ɾػೳղઆ Diagnostics

©2019 Wantedly, Inc. Runtime statistics and events runtime, runtime/debug ‣
SVOUJNFʹऔΕΔॾʑͷ਺ࣈ - runtime.ReadMemStats - debug.ReadGCStats - debug.Stack - debug.WriteHeapDump - runtime.NumGoroutine ‣ SVOUJNFͷΠϕϯτʢTZTDBMM΍($ ͦͷଞ͍Ζ͍ΖʣΛ  AHPUPPMUSBDFAίϚϯυͰWJTVBMJ[FͰ͖Δ ࢓༷ɾػೳղઆ Diagnostics

©2019 Wantedly, Inc. Concurrency is not parallelism https://blog.golang.org/concurrency-is-not-parallelism ‣ 3PC1JLFʹΑΔฒྻͱฒߦͷ࿩ʢʣ
͜ͷ࣌఺Ͱ͸·ͩ(P͸ʹͳ͍ͬͯͳ͍ ‣ ͜ͷ࿩ ฒߦॲཧ Concurrency is not parallelism Slide https://talks.golang.org/2012/waza.slide

©2019 Wantedly, Inc. Concurrency vs. parallelism ฒߦॲཧ Concurrency is not
parallelism

©2019 Wantedly, Inc. Concurrency vs. parallelism ‣ $PODVSSFODZ͸ʢݟ͔͚ͤͰ΋͍͍͔Βʣॲཧ͕ಉ࣌ʹߦ͑ΔΑ͏ͳߏ଄ ࣮ࡍʹಉ࣌ʹߦΘΕ͍ͯΔ͔͸ؔ܎ͳ͍
‣ 1BSBMMFMJTN͸࣮ࡍʹॲཧ͕ಉ࣌ʹߦ͑Δͱ͍͏͜ͱ ‣ ؔ৺͕ҧ͏ͷͰɺʮ$PODVSSFODZͰ͋Γ1BSBMMFMJTNͰ΋͋Δʯ΋͋Γ͏Δ ※ ॾઆ͋Γ·͢ɻڐͯ͠ɻ ฒߦॲཧ Concurrency is not parallelism

©2019 Wantedly, Inc. Advanced Go Concurrency Patterns https://blog.golang.org/advanced-go-concurrency-patterns ‣ 4BNFFS"KNBOJ
4BKNBOJ ʹΑΔฒߦॲཧͷ࣮ફྫͷ঺հʢʣ HPSPVUJOFDIBOOFMTFMFDUͳͲΛ;ΜͩΜʹ࢖ͬͨྫ ฒߦॲཧ Advanced Go Concurrency Patterns Slide https://talks.golang.org/2013/advconc.slide

©2019 Wantedly, Inc. ฒߦॲཧ Advanced Go Concurrency Patterns Snippets are
from https://talks.golang.org/2013/advconc.slide for { if s.closed { close(s.updates) return } items, next, err := s.fetcher.Fetch() if err != nil { s.err = err time.Sleep(10 * time.Second) continue } for _, item := range items { s.updates <- item } if now := time.Now(); next.After(now) { time.Sleep(next.Sub(now)) } } func (s *naiveSub) Close() error { s.closed = true return s.err } ‣ ࠨͷίʔυʹ͸όά͕Օॴ͋Γ·͢ɻͲ͜Ͱ͠ΐ͏ʁ

from https://talks.golang.org/2013/advconc.slide for { if s.closed { close(s.updates) return } items, next, err := s.fetcher.Fetch() if err != nil { s.err = err time.Sleep(10 * time.Second) continue } for _, item := range items { s.updates <- item } if now := time.Now(); next.After(now) { time.Sleep(next.Sub(now)) } } func (s *naiveSub) Close() error { s.closed = true return s.err } ‣ ࠨͷίʔυʹ͸όά͕Օॴ͋Γ·͢ɻͲ͜Ͱ͠ΐ͏ʁ ‣ ʜΈ͍ͨͳײ͡Ͱɺ࣮ࡍͷίʔυͷόάΛ௵͍͖ͯ͠ͳ͕Β  ฒߦॲཧΛ࣮૷͢ΔͨΊͷύλʔϯΛ঺հͯ͘͠ΕΔ 

from https://talks.golang.org/2013/advconc.slide for { if s.closed { close(s.updates) return } items, next, err := s.fetcher.Fetch() if err != nil { s.err = err time.Sleep(10 * time.Second) continue } for _, item := range items { s.updates <- item } if now := time.Now(); next.After(now) { time.Sleep(next.Sub(now)) } } func (s *naiveSub) Close() error { s.closed = true return s.err } ‣ ࠨͷίʔυʹ͸όά͕Օॴ͋Γ·͢ɻͲ͜Ͱ͠ΐ͏ʁ ‣ ʜΈ͍ͨͳײ͡Ͱɺ࣮ࡍͷίʔυͷόάΛ௵͍͖ͯ͠ͳ͕Β  ฒߦॲཧΛ࣮૷͢ΔͨΊͷύλʔϯΛ঺հͯ͘͠ΕΔ  ౴͑͸ࣗ෼Ͱݟ͚ͭͯͶ

©2019 Wantedly, Inc. Go Concurrency Patterns: Pipelines and cancellation https://blog.golang.org/pipelines
‣ 4BNFFS"KNBOJ 4BKNBOJ ʹΑΔύΠϓϥΠϯॲཧͷ࿩ʢʣ ‣ 1JQFMJOFॲཧ͸͍͍ͩͨ͜͏͍͏ͷΛΠϝʔδ͢Δͱྑ͍΍ͭ ͜Ε΋࣮ࡍͷίʔυΛྫʹͭͭ͠ɺ  ඞཁͳཁૉΛ࣮͋͛ͯ૷͍ͯ͘͠ ฒߦॲཧ Go Concurrency Patterns: Pipelines and cancellation Image from https://talks.golang.org/2012/waza.slide

©2019 Wantedly, Inc. PipelineॲཧͰߟྀ͢΂͖͜ͱ ‣ 'BOPVU ‣ 'BOJO ‣ ऴྃॲཧ
‣ $BODFMॲཧ ฒߦॲཧ Go Concurrency Patterns: Pipelines and cancellation

©2019 Wantedly, Inc. PipelineॲཧͰߟྀ͢΂͖͜ͱ ‣ 'BOPVU ॲཧ͢ΔϫʔΧʔͷ਺Λ૿΍͢ʢDGTDBMFPVUʣ ‣ 'BOJO
ฒྻʹॲཧͨ݁͠ՌΛগ਺ͷϫʔΧʔʹू໿ͯ͠ॲཧ ‣ ऴྃॲཧ ‣ $BODFMॲཧ ฒߦॲཧ Go Concurrency Patterns: Pipelines and cancellation

©2019 Wantedly, Inc. PipelineॲཧͰߟྀ͢΂͖͜ͱ ‣ 'BOPVU ‣ 'BOJO ‣ ऴྃॲཧ
ऴྃ͢Δ·͑ʹɺॲཧதͷϝοηʔδ͸શ෦ऴΘΔ·Ͱ଴ͭʢDGHSBDFGVMTIVUEPXOʣ ‣ $BODFMॲཧ ֎෦͔ΒͷऴྃγάφϧΛड͚औΕΔΑ͏ʹ͠Α͏ʢFH4*(5&3. λΠϜΞ΢τ DGDPOUFYU$POUFYUʣ ฒߦॲཧ Go Concurrency Patterns: Pipelines and cancellation

©2019 Wantedly, Inc. What's in a name? https://talks.golang.org/2014/names.slide ‣ "OESFX(FSSBOE
BEH ʹΑΔɺ(Pʹ͓͚Δྑ໊͍લ෇͚ʹؔ͢Δ࿩ʢʣ ‣ ʮͲ͏͍͏໊લΛ͚ͭΕ͹Α͍͔ʁʯΛཁૉผʹ঺հ͍ͯ͠Δ FH ؔ਺ͷҾ਺໊͸υΩϡϝϯτʹͳΔͷͰɺܕ͚ͩઆ໌Ͱ͖ͳ͍৔߹͸ҙຯͷ͋Δ໊લΛ͚ͭΑ͏ A"GUFS'VOD E%VSBUJPO GGVOD 5JNFSAA6OJY TFD OTFDJOU 5JNFA ؔ਺ͷϨγʔό໊͸ܕ໊Λ൓өͨ͠ʙจࣈ͘Β͍ʹ͠Α͏ Naming What's in a name? Image from https://talks.golang.org/2012/waza.slide

©2019 Wantedly, Inc. Package names https://blog.golang.org/package-names ‣ (Pͷྑ͍ύοέʔδ໊ͷ࿩ʢʣ ‣ ʮྑ͍ύοέʔδ໊ʯʮѱ͍ύοέʔδ໊ʯΛ͍ΖΜͳྫΛڍ͛ͭͭઆ໌͍ͯ͘͠
FH ⭕୹ͯ͘Θ͔Γ΍͍͢UJNF MJTU IUUQ ❌ޠҎ্࢖Θͳ͍DPNQVUF4FSWJDF$MJFOU QSJPSJUZ@RVFVF ⭕ʢઅ౓͋ΔʣུޠTUSDPOW TZTDBMM GNU Naming What's in a name? Image from https://talks.golang.org/2012/waza.slide

©2019 Wantedly, Inc. Package names ‣ ίϯςϯπͷ໊લ΍ύοέʔδͷύεͷ໋໊ʹ͍ͭͯ΋ݴٴ͕͋Δ FH
৑௕ʹ͠ͳ͍❌IUUQ)5514FSWFS ⭕IUUQ4FSWFS ᐆດ͕͞ͳ͚Ε͹ύοέʔδ໊͸͔Ϳͬͯ΋ྑ͍SVOUJNFQQSPG OFUIUUQQQSPG ‣ ʮ͜Ε͸ྑ͘ͳ໊͍લʂʯνΣοΫϦετ FH ҙຯͷͳ໊͍લ͸μϝVUJM DPNNPO (͢΂ͯͷ"1*Λύοέʔδʹू໿͢Δͷ͸μϝBQJ UZQFT JOUFSGBDFT ͜͜Ͱ͍͏"1*͸8FC"1*ͷ͜ͱͰ͸ͳ͍  ʢҙຯ͕޿͍ͷ͸ͦͷͱ͓Γ͕ͩɺίϯςΩετʹΑͬͯ͸ڐ͞ΕΔͷͰ͸ͱݸਓతʹ͸ߟ͍͑ͯΔʣ Naming What's in a name? Image from https://talks.golang.org/2012/waza.slide

©2019 Wantedly, Inc. References Specifications and internal ‣ (P%BUB4USVDUVSFT*OUFSGBDFT
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今あらためて読み直したい Go 基礎知識 その2 / golang.tokyo #25

今あらためて読み直したい Go 基礎知識 その2 / golang.tokyo #25

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今あらためて読み直したい Go 基礎知識その2 / golang.tokyo #25

今あらためて読み直したい Go 基礎知識その2 / golang.tokyo #25