Goで軽量マークアップ言語のパーサーを書く / Writing a parser with Go

そうだGo、京都 (https://go-kyoto.connpass.com/event/55599/) で発表した資料です。

Transcript

1. GoͰܰྔϚʔΫΞοϓݴޠ
   ͷύʔαʔΛॻ͘
   id:aereal
   

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2. ܰྔϚʔΫΞοϓݴޠͱ͸
   • ҎԼ LML = Lightweight Markup Language
   • HTML΍XMLͱϓϨʔϯςΩετͷதؒ
   • Markdown, Textile, ͸ͯͳه๏, etc.
   

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3. ܰྔϚʔΫΞοϓݴޠͱ͸
   • ҎԼ LML = Lightweight Markup Language
   • HTML΍XMLͱϓϨʔϯςΩετͷதؒ
   • Markdown, Textile, ͸ͯͳه๏, etc.
   

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4. GoͰ͸ͯͳه๏ͷ
   ύʔαʔΛॻ͘
   id:aereal
   

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5. ࣗݾ঺հ
   • id:aereal
   • Twitter: aereal
   • GitHub: aereal
   • גࣜձࣾ͸ͯͳ

   ΞϓϦέʔγϣϯΤϯδχΞ
   

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6. !͓͜ͱΘΓ!
   • ࠓճ঺հ͢Δ͸ͯͳه๏ύʔαʔ͸

   ϓϥΠϕʔτϫʔΫͰ͢
   • ͸ͯͳͷαʔϏεʹ࠾༻͞ΕΔ͔ͳͲ͸

   ͢΂ͯະఆͰ͢
   

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7. ࢀߟ৘ใ
   • ͜ͷࢿྉͰ঺հ͢Δ৘ใ͸͢΂ͯ 2017gokyoto ͱ
   ͍͏λάΛ͚ͭͯϒοΫϚʔΫ͍ͯ͠·͢
   • http://b.hatena.ne.jp/aereal/2017gokyoto/
   

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8. ͸ͯͳه๏ͱ͸
   • ͸ͯͳ͕ఏڙ͢ΔαʔϏεͷҰ෦Ͱ࢖͑ΔLML
   • ͸ͯͳϒϩάɺ͸ͯͳμΠΞϦʔ
   • org-modeͱͪΐͬͱࣅ͍ͯΔ
   

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9. ͸ͯͳه๏ͷྫ
   * ݟग़͠1
   ** ݟग़͠2
   - Ruby
   - Perl
   - Go
   + ى
   + ঝ
   + స
   + ݁
   

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10. ͳͥύʔαʔΛॻ͘?
    • طʹಈ͍͍ͯΔ΋ͷʹखΛՃ͑ΔͷͰ͸μϝ?
    • ͳͥ͸ͯͳه๏?
    • ͳͥGoͰ?
    

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11. Ϟνϕʔγϣϯ
    • طଘͷ࣮૷ʹखΛՃ͑Δͷ͸Ή͔͍ͣ͠
    • ͸ͯͳه๏Λύʔε͍ͨ͠χʔζ͸͋Δ!
    • Go͕ॻ͖͔ͨͬͨ
    

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12. طଘͷ࣮૷ʹखΛՃ͑Δͷ͸
    Ή͔͍ͣ͠
    • ܗࣜతͳఆ͕ٛͳ͍ = ಈ͘ίʔυ͕࢓༷
    • ਖ਼نදݱ
    

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13. ͸ͯͳه๏Λύʔε͍ͨ͠
    χʔζ͸͋Δ!
    • ͸ͯͳάϧʔϓͰීஈ͔Βॻ͍͍ͯΔ
    • ͸ͯͳϒϩάͰ೔هΛॻ͘ͷ͕झຯ
    • →͸ͯͳه๏ʹ೔ৗతʹ৮Ε͍ͯΔ
    • Markdown΁ͷม׵ (...)
    

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14. Go͕ॻ͖͔ͨͬͨ
    • ීஈ͸Perl΍JavaScriptɺͨ·ʹScala
    • ۀ຿ͱҟͳΔίϯςΩετͰίʔυΛॻ͖͔ͨͬͨ
    

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15. ͪΐ͏Ͳ͍͍໨ඪ
    • Ͱ͖Δ͜ͱɺ΍Γ͍ͨ͜ͱɺؔ৺ͷ͋Δ͜ͱ͕

    ͍͍͔Μ͡ʹόϥϯε͞Ε͍ͯΔ
    • WebͱςΩετϓϩηογϯά
    • খ໨ඪΛੵΈॏͶ͍͚ͯΔ
    • ʮࠓ೔͸͜ͷه๏Λ௥Ճ͠Α͏ʯ
    

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16. 108͋Δ͸ͯͳه๏ύʔαʔ
    • ͸ͯͳμΠΞϦʔ
    • ͸ͯͳάϧʔϓ
    • Text-Hatena (CPAN)
    • Text-Xatena
    • chris4403/WikiTextConverter
    • ...
    

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17. 108͋Δ͸ͯͳه๏ύʔαʔ
    • ͦΕͧΕඍົʹ࢓༷͕ҟͳΔ
    • ৽͘͠࡞ΒΕͨ΋ͷ΄ͲεʔύʔηοτͷఆٛΛ

    ࢼΈΔ܏޲͕͋Δ
    

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18. ܗࣜతͳఆٛΛ༩͍͑ͨ
    • ࣮૷ͱఆٛΛૄʹ͍ͨ͠
    • ఆ͚ٛͩΛࢀর͍ͨ͠
    • ͤΊͯCommonMark͘Β͍ͷ΋ͷ͸……
    • (ͱ͸͍࣮͑૷ͱϦϯΫͤ͞ΒΕΔ΄͏͕Α͍)
    

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19. aereal/go-text-hatena
    https://github.com/aereal/go-text-hatena
    

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20. ࣮૷ͨ͠ه๏
    • ݟग़͠
    • Ϧετ
    • Ҿ༻
    • HTTPه๏ (Ұ෦)
    

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21. ໨ࢦ͢ͱ͜Ζ
    • ϙʔλϒϧͰ͋Δ͜ͱ
    • ݴޠʹґΒͣར༻Ͱ͖Δ
    • ར༻ऀ͕೚ҙͷHTMLม׵ϧʔϧΛద༻Ͱ͖Δ
    • ࣮૷ͱఆٛΛૄʹ
    • ఆٛΛ੩తʹࢀরͰ͖Δ
    • ࣮૷ݴޠ (Go) ͷ஌͕ࣝͳͯ͘΋งғؾ͸௫ΊΔ
    

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22. ࣮૷
    • GoͰೖग़ྗΛΠϯλʔϑΣʔεͱ͢ΔόΠφϦ
    • → ݴޠʹґΒͣར༻Ͱ͖Δ
    • ASTΛJSONͰग़ྗ͢Δ͚ͩ
    • → ར༻ऀ͕೚ҙͷHTMLม׵ϧʔϧΛద༻ (࣮૷)
    Ͱ͖Δ
    

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23. ࣮૷
    • goyaccΛ࢖͍YACCͰจ๏ఆٛ
    • → ఆٛΛ੩తʹࢀরͰ͖Δ (parser.go.y)
    • ࣮૷ݴޠ (Go) ͷ஌͕ࣝͳͯ͘΋งғؾ͸௫ΊΔ
    

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24. HTML΁ͷม׵
    • αʔϏεʹΑͬͯͲΕ͘Β͍HTMLͷೖྗΛ

    ڐ༰͢Δ͔ͷํ਑͕ҟͳΔ
    • ͸ͯͳϒϩά͸ࣗ༝͕ͩɺ͸ͯͳμΠΞϦʔ͸

    ϗϫΠτϦετܗࣜ
    • ηΩϡϦςΟ্ͷࣄ৘
    

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25. ม׵σϞ
    • aereal/sketch-hatena-notation-api
    

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26. GoͰύʔαʔΛॻ͘
    

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27. ࢖ͬͨπʔϧ
    • Go
    • goyacc
    • text/scanner
    

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28. goyacc
    • yaccͷGo൛
    • ࠷ۙ go tool ͔Β֎Εͨ
    • go get golang.org/x/tools/cmd/goyacc
    

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29. yacc
    • ύʔαʔδΣωϨʔλʔ
    • BNF
    • ఆٛʹରͯ͠ίʔϧόοΫΛॻ͍͍ͯ͘
    • ؐݩͱΞΫγϣϯͱݺ͹ΕΔ
    • ଎शyacc͕͓͢͢Ί
    • ࣮૷ྫͱͯ͠ mattn/streeem ΋ࢀߟʹͳΔ
    

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30. yaccͷ͍͍ͱ͜Ζ
    • BNFʹΑΔఆٛͱɺؐݩ͢Δίʔυ͕෼཭Ͱ͖Δ
    • ݴޠ಺DSLΛ࢖͏ύʔαʔίϯϏωʔλʔΑΓ

    ଞͷਓʹݺΜͰ΋Β͍΍͍͢ؾ͕͢Δ
    

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31. yaccͷඍົͳͱ͜Ζ
    • *.go.y ͰΤσΟλͷࢧԉ͕ड͚ΒΕͳ͍
    • ͏·͍͜ͱઃఆͨ͠ΒͰ͖ͦ͏Ͱ͸͋Δ
    • ࣈ۟ղੳ͸ࣗ෼ͰؤுΔඞཁ͕͋Δ
    • GoͰ͸ text/scanner ͱ͍͏ඪ४ϥΠϒϥϦ͕

    ͋ΔͷͰָͰ͖Δ
    

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32. ίʔυΛಡΜͰΈΔ
    • lex.go
    • parser.go.y
    • parser_test.go
    

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33. ·ͱΊ
    

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34. ·ͱΊ
    • ͸ͯͳه๏ύʔαʔΛGoͰॻ͍ͨ
    • Goʹ͸goyacc΍text/scannerͳͲ

    ߏจղੳ΍ࣈ۟ղੳͷͨΊͷπʔϧ͕ἧ͍ͬͯΔ
    

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35. ࢀߟ৘ใ
    • ͜ͷࢿྉͰ঺հ͢Δ৘ใ͸͢΂ͯ 2017gokyoto ͱ
    ͍͏λάΛ͚ͭͯϒοΫϚʔΫ͍ͯ͠·͢
    • http://b.hatena.ne.jp/aereal/2017gokyoto/
    

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