Slide 1
Slide 1 text
GoͰόΠφϦΛಡΉ
+α
Fukuoka.go #10
pixiv.inc
Atsushi Takayama
Slide 2
Slide 2 text
• ߴࢁԹ / edvakf
ϐΫγϒגࣜձࣾ ࣥߦһCTO ݉ ԬΦϑΟεϚωʔδϟʔ
• Go, Ruby, JavaScript, Scala, PHP
ࣗݾհ
Slide 3
Slide 3 text
func init() {
Slide 4
Slide 4 text
GoͰόΠφϦΛಡΉ
ͱ͍͏ྫΛݩʹɺGoͷ͜ͱΛΖ͏
Slide 5
Slide 5 text
όΠφϦΛಡΊΔͱ
Slide 6
Slide 6 text
ΧοίΠΠ
Slide 7
Slide 7 text
% cat testdata/hello.wasm | xxd -g1 | head -n 30
00000000: 00 61 73 6d 0d 00 00 00 01 ae 83 80 80 00 30 60 .asm..........0`
00000010: 01 7f 01 7f 60 03 7f 7f 7f 01 7f 60 01 7c 01 7f ....`......`.|..
00000020: 60 02 7f 7f 01 7f 60 03 7f 7f 7f 00 60 05 7f 7f `.....`.....`...
00000030: 7f 7f 7f 01 7f 60 08 7f 7f 7f 7f 7f 7f 7f 7f 01 .....`..........
00000040: 7f 60 01 7f 00 60 06 7f 7f 7f 7f 7f 7f 01 7f 60 .`...`.........`
00000050: 02 7f 7f 00 60 04 7f 7f 7f 7f 01 7f 60 00 00 60 ....`.......`..`
00000060: 04 7f 7f 7f 7f 00 60 06 7f 7f 7f 7f 7f 7f 00 60 ......`........`
00000070: 05 7f 7f 7f 7f 7f 00 60 07 7f 7f 7f 7f 7f 7f 7f .......`........
00000080: 01 7f 60 06 7f 7f 7f 7f 7f 7c 01 7f 60 05 7f 7f ..`......|..`...
00000090: 7e 7f 7f 00 60 0b 7f 7f 7f 7f 7f 7f 7f 7f 7f 7f ~...`...........
000000a0: 7f 01 7f 60 0f 7f 7f 7f 7f 7f 7f 7f 7f 7f 7f 7f ...`............
000000b0: 7f 7f 7f 7f 00 60 03 7f 7f 7f 01 7d 60 07 7f 7f .....`.....}`...
000000c0: 7f 7f 7f 7f 7f 00 60 0a 7f 7f 7f 7f 7f 7f 7f 7f ......`.........
000000d0: 7f 7f 00 60 03 7f 7f 7f 01 7c 60 00 01 7f 60 04 ...`.....|`...`.
000000e0: 7f 7f 7f 7f 01 7e 60 05 7f 7f 7f 7f 7e 01 7f 60 .....~`.....~..`
000000f0: 05 7f 7f 7f 7f 7c 01 7f 60 0c 7f 7f 7f 7f 7f 7f .....|..`.......
00000100: 7f 7f 7f 7f 7f 7f 01 7f 60 10 7f 7f 7f 7f 7f 7f ........`.......
Slide 8
Slide 8 text
;Ή;Ή
Slide 9
Slide 9 text
}
Slide 10
Slide 10 text
func main() {
Slide 11
Slide 11 text
͜͏ͬͯಡΉͷਏ͍ͷͰ
Slide 12
Slide 12 text
ߏମʹϚοϐϯά͠·͢
Slide 13
Slide 13 text
type Module struct {
Header ModuleHeader
Sections []Section
}
type ModuleHeader struct {
Magic [4]byte
Version uint32
}
type Section struct {
...
}
Slide 14
Slide 14 text
ͪΖΜ͏ͷ
Slide 15
Slide 15 text
type Reader interface {
Read(p []byte) (n int, err error)
}
ετϦʔϜΛҙࣝ͢Δͱ͖ io.Reader Λ͏
io.Reader
Slide 16
Slide 16 text
// 4όΠτΛio.Reader͔ΒಡΈࠐΉ
var buf [4]byte
num, err := r.Read(buf[:])
[4]byte ʮྻʯ
buf[0:4] ͱ͔ buf[:] ͰྻͷҰ෦ͷϙΠϯλʔΛؚΉʮεϥΠεʯ
ReadʹͤΔͷʮεϥΠεʯ
NόΠτಡΉ
Slide 17
Slide 17 text
import "encoding/binary"
var num int64
err := binary.Read(r, binary.LittleEndian, &num)
binary.Read ͷୈࡾҾ interface{}
৭ΜͳܕͷϙΠϯλʔ͕ͤΔ
int/floatΛಡΉ
Slide 18
Slide 18 text
int/float͚ͩͰͳ͘
Slide 19
Slide 19 text
b := []byte{0x18, 0x2d, 0x44, 0x54, 0xfb, 0x21, 0x09, 0x40, 0xff, 0x01, 0x02, 0x03,
0xbe, 0xef}
r := bytes.NewReader(b)
var data struct {
PI float64
Uate uint8
Mine [3]byte
Too uint16
}
err := binary.Read(r, binary.LittleEndian, &data)
ߏମΛؙ͝ͱಡΉ
Slide 20
Slide 20 text
binary.Readศར
Slide 21
Slide 21 text
fmt.Printf("%v\n", data)
// => {3.141592653589793 255 [1 2 3] 61374}
fmt.Printf("%+v\n", data)
// => {PI:3.141592653589793 Uate:255 Mine:[1 2 3] Too:61374}
fmt.Printf("%#v\n", data)
// => struct { PI float64; Uate uint8; Mine [3]uint8; Too uint16 }{PI:
3.141592653589793, Uate:0xff, Mine:[3]uint8{0x1, 0x2, 0x3}, Too:0xefbe}
fmtͷ%v
Slide 22
Slide 22 text
LLฒͷ͍উख
Slide 23
Slide 23 text
Α͘ݴΘΕΔGoͷັྗ
Slide 24
Slide 24 text
ඪ४ϥΠϒϥϦ͕γϯϓϧ͔ͭڧྗ
͓Θ͔Γ͍͚ͨͩͨͩΖ͏͔ʁ
Slide 25
Slide 25 text
Α͘ݴΘΕΔGoͷܽ
Slide 26
Slide 26 text
Τϥʔॲཧ͕DRY͡Όͳ͍
Slide 27
Slide 27 text
var buf [4]byte
num, err := r.Read(buf[:])
if err != nil {
// Τϥʔॲཧ
}
var num int64
err = binary.Read(r, binary.LittleEndian, &num)
if err != nil {
// Τϥʔॲཧ
}
err = binary.Read(r, binary.LittleEndian, &data)
if err != nil {
// Τϥʔॲཧ
Slide 28
Slide 28 text
Slide 29
Slide 29 text
type decoder struct {
r io.Reader
err error
}
func (d *decoder) read(r io.Reader, buf []byte) {
if d.err != nil || len(buf) == 0 {
return
}
_, d.err = r.Read(buf)
}
// https://github.com/sbinet/wasm/blob/master/decoder.go
Slide 30
Slide 30 text
• Rob Pikeઌੜᐌ͘ɺ
• Errors are values (ΤϥʔͨͩͷฦΓ)
• Τϥʔྫ֎ͱҧ͏ɻνΣοΫ͢ΔͷͰͳ͘ɺ
దʹॲཧͤΑ
• https://youtu.be/PAAkCSZUG1c?t=16m14s
Slide 31
Slide 31 text
}
Slide 32
Slide 32 text
ͦͦԿ࡞ͬͯΔͷʁ
Slide 33
Slide 33 text
WebAssemblyʹৄ͘͠ͳΓ͔ͨͬͨ
Slide 34
Slide 34 text
Slide 35
Slide 35 text
• CGoΛWasmʹίϯύΠϧ͢ΔͷطʹͰ͖Δ
• ࠓޙͨ͘͞Μͷݴޠ͕WasmʹίϯύΠϧͰ͖ΔΑ͏
ʹͳΔͣ
• Goͷ্ͰWasmΛ࣮ߦ͢ΔະདྷདྷΔͣ
Slide 36
Slide 36 text
Wasm→Ruby ISeqίϯύΠϥʔ
mRuby→WasmίϯύΠϥʔ
Slide 37
Slide 37 text
Ӷҙ࡞த
Slide 38
Slide 38 text
• https://github.com/edvakf/wasm
• https://github.com/edvakf/wagyu
• ͠ͳͯ͘ɺ࣮༻త͡Όͳͯ͘ɺษڧ͢Δ͜ͱ
ࣗମָ͕͚͠Ε͍͍ɻͦΜͳϓϩάϥϜΛॻ͜͏ͱ
ࢥͬͯͬͯ·͢ɻ
Slide 39
Slide 39 text
os.Exit(0)