The reason for using reason

https://ml-lang.connpass.com/event/58151/

Transcript

1. 5IF
   SFBTPO
   GPS
   VTJOH
   SFBTPO N[Q .-ษڧձ
   
2. ཁ໿ .PEFSO
   +BWB4DSJQU
   ❤
   .-
   GFBUVSFT
   Ͱ΋ಋೖ͸େม 0$BNMΛ+BWB4DSJQUͬΆ͘͠Α͏
4. Ҿ༻ݩ
   3*05
   "
   3FBDUMJLF
   VTFS
   JOUFSGBDF
   NJDSPMJCSBSZ
   IUUQNJLFXBSEOFUUBMLSJPUKT
6. class Greeting extends React.Component { render() { return <h1>Hello</h1>; } } 3FBDU
   WJFXͷߏங
7. 3FEVY
   ঢ়ଶ؅ཧ ભҠؔ਺Λఆٛ͠ঢ়ଶΛ؅ཧ͢Δ
   ͜ͷؔ਺ΛSFEVDFSΛݺͿ state -> action -> state
8. function counter(state = 0, action) { switch (action.type) { case 'INCREMENT': return state + 1 case 'DECREMENT': return state - 1 default: return state } } ྫ
   DPVOUFS
   SFEVDFS { type: "INCREMENTAL" }
9. function todo(state, action) { switch (action.type) { case 'TOGGLE': if(state.id == action.id) { return {...state , completed: !state.completed } } else { return state } default: return state } } ྫ
   UPEP
   SFEVDFS { type: 'TOGGLE', id: 42 } { id: 42, name: "create slide", completed: false, ... }
10. SFEVDFS
    JEJPN UZQF͕Yͷͱ͖ɺZͱ͍͏߲໨Λ࣋ͭ
    ঢ়ଶΛίϐʔ͠ɺҰ෦͚ͩߋ৽͢Δ ˠ
    όϦΞϯτܕͬΆ͍ ˠ
    ϨίʔυܕͬΆ͍
11. .-༝དྷͷػೳͷಋೖ ύλʔϯϚον
    .BZCFϞφυ
    ඇಉظϞφυ
    ੩తܕݕࠪ
12. + 2016 Ҿ༻ݩ
    5IF
    %BXO
    PG
    3FBTPO
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13. ✨ཧ૝ͷݴޠ✨ όϦΞϯτϨίʔυܕ͕͋Δ
    ύλʔϯϚον͕͋Δ
    ੩తܕݕ͕ࠪ͋Δ
    +BWB4DSJQU͕ੜ੒Ͱ͖Δ
14. JS developer trying to grasp OCaml syntax Ҿ༻ݩ
    5IF
    %BXO
    PG
    3FBTPO
    IUUQTTBOEFSTQJFTHJUIVCJPTMJEFTEBXOPGSFBTPOQEG
15. JavaScript OCaml Flow Reason Adopting features of ML Becoming familiar to JS developers Syntax + tooling A lot of work Ҿ༻ݩ
    5IF
    %BXO
    PG
    3FBTPO
    IUUQTTBOEFSTQJFTHJUIVCJPTMJEFTEBXOPGSFBTPOQEG
16. 3FBTPO͕΍ͬͯΔ͜ͱ
17. #VDLMF4DSJQUͱͷ࿈ܞ 0$BNM͔Β+BWB4DSJQUΛੜ੒͢ΔίϯύΠϥ
    IUUQHJUIVCDPNCMPPNCFSHCVDLMFTDSJQU function fact(n) { if (n !== 0) { return imul(n, fact(n - 1 | 0)); } else { return 1; } } let rec fact = function | 0 -> 1 | n -> n * fact (n - 1) 0$BNM +BWB4DSJQU
18. 'use strict'; var Pervasives = require("bs-platform/lib/js/pervasives"); var Http = require("http"); var hostname = "127.0.0.1"; function create_server(http) { var server = http.createServer(function (_, resp) { resp.statusCode = 200; resp.setHeader("Content-Type", "text/plain"); return resp.end("Hello world\n"); }); return server.listen(3000, hostname, function () { console.log("Server running at http://" + (hostname + (":" + (Pervasives.string_of_int(3000) + "/")))); return /* () */0; }); } create_server(Http); IVNBO
    SFBEBCMF
    DPEF
19. Ҿ༻ݩ
    0$BNM
    
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20. let greeting = "hello!"; let name = "mzp"; ..... จ๏
    ม਺ଋറ
21. if (showMenu) { displayMenu (); }; จ๏
    ৚݅෼ذ
22. switch data { | GoodResult theMessage => "Success! " ^ theMessage | BadResult errorCode => "Something's wrong. The error code is: " ^ (string_of_int errorCode) }; จ๏
    ύλʔϯϚον
23. ύοέʔδϚωʔδϟʔ OQNΛར༻͢Δ
    PQBN͸࢖Θͳ͍
    OQN
    JOTUBMM
    CTQMBUGPSN
    Ͱ0$BNMͷϏ ϧυ͕࢝·Δ
    
    
24. ίʔυิ׬
    NFSMJO
25. ΤσΟλ֦ு
26. #FUUFS&SSPST Ҿ༻ݩ
    IUUQTHJUIVCDPNSFBTPONM#FUUFS&SSPST
27. SFE Ҿ༻ݩ
    IUUQTHJUIVCDPNSFBTPONMSFE
28. ༨ஊ
    3FBTPOͱ͍͏໊લ ؔ࿈ϓϩμΫτ͕શ෦Ұൠ໊ࢺ
 qPX
    JOGFS
    SFBTPO
    
    FYBNQMFʹSFBTPOPGMJGF͕͋Δ
29. 3FBTPOͷར༻ྫ
30. IUUQTUXJUUFSDPNMPZPMOZTUBUVT 'BDFCPPL
    .FTTBOHFSͷ͸
    3FBTPOʹஔ͖׵͑ΒΕͯΔ
31. Meanwhile at… Concurrent React Prototype in OCaml @jordwalke Ҿ༻ݩ
    5IF
    %BXO
    PG
    3FBTPO
    IUUQTTBOEFSTQJFTHJUIVCJPTMJEFTEBXOPGSFBTPOQEG
33. 3FBTPOͷΑ͍໘
34. let redux state = function | `Toggle id -> if state.id = id then { state with complete=not state.complete } else state | _ -> state ύλʔϯϚον࠷ߴ
35. Ϗϧυ଎౓
36. let maybeSay (s: string Js.null) = Js.Null.iter s (fun message -> Js.log message) let maybeSay (s: string Js.undefined) = Js.Undefined.iter s (fun message -> Js.log message) OVMMVOEFpOFE
37. take_if context ~f:(function `DelayedInc -> Some () | _ -> None) >>= (fun () -> call (delay 1000)) >>= (fun () -> put context `Inc) DBMMCBDL
    IFMM
38. 3FBTPOͷͭΒ͍໘
39. Πϯετʔϧ࣌ؒͷ૿Ճ
40. external request : config -> response Js.Promise.t = "get" [@@bs.module "axios"]; external get : string -> config Js.null -> response Js.Promise.t = "get" [@@bs.module "axios"]; external delete: string -> config Js.null -> response Js.Promise.t = "delete" [@@bs.module "axios"]; external head: string -> config Js.null -> response Js.Promise.t = "head" [@@bs.module "axios"]; external post: string -> 'a Js.null -> config Js.null -> response Js.Promise.t = "post" [@@bs.module "axios"]; external put: string -> config Js.null -> response Js.Promise.t = "put" [@@bs.module "axios"]; external patch: string -> config Js.null -> response Js.Promise.t = "patch" [@@bs.module "axios"]; ܕఆ͕ٛେม
41. let expect_array json = switch (Js.Json.reifyType json) { | Js.Json.Array, data -> swtich (Js.Json.reifyType data) { ... } | _ -> failwith "unexpected response type" } +40/͔ΒͷσʔλऔΓग़͠
42. type tree = | Leaf | Node of int * tree * tree (* Leaf --> 0 *) (* Node(a,b,c) --> [a,b,c]*) όϦΞϯτͷϥϯλΠϜදݱ
43. Α͘Θ͔ͬͯͳ͍෦෼
44. WJNͷϋΠϥΠτ ΩʔϫʔυͷϋΠϥΠτ͕ෆ׬શ ????
45. +4$BNM Ҿ༻ݩ
    IUUQTHJUIVCDPNGBDFCPPLFYQFSJNFOUBM+4$BNM
46. FTZ ZBSOͷGPSL
    μ΢ϯϩʔυͱϏϧυ͕۠ผ͞Ε͍ͯΔ
47. PQBNϒϦοδ
48. ࢀߟจݙ BXFTPNF
    SFBTPO
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    %BXO
    PG
    3FBTPO
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    3FBTPO
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    #VDLMF4DSJQU
    NBOVBM
 IUUQCVDLMFTDSJQUHJUIVCJPCVDLMFTDSJQU.BOVBMIUNM
49. ·ͱΊ +BWB4DSJQUʹ͸.-ͷػೳ͕ඞཁ
    ಋೖ͸େมͩ͠ɺ0$BNM࢖ͬͨ΄͏͕ ͍͍
    ͦͷ··͸ͭΒ͍ͷͰ࢖͍΍ͨ͘͢͠ͷ ͕3FBTPO