The Return of Stream I/O

The Frontend community is remarkably shifting towards functional programming, with tools like React, Redux, Immutable.js and Elm becoming mainstream. In the early years of Haskell, there were three I/O models: Monads, Continuations, and Streams. While the Monadic I/O has been established as the standard in Haskell, we are seeing the resurgence of variations of Stream I/O in Frontend, through tools like Cycle.js and Elm. In this talk we will explore the benefits and downsides of Stream I/O, and what it promises for the future.

Transcript

1. @andrestaltz
   The Return of Stream I/O
   

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2. Cycle.js.org
   A functional and reactive JavaScript framework 

   for cleaner code
   

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14. Haskell
    A pure functional
    programming language
    

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15. Haskell
    A pure functional
    programming language
    Logic
    Effects
    

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16. Haskell
    A pure functional
    programming language
    Logic
    Effects
    

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17. Logic
    Effects
    Monadic I/O
    Stream I/O
    Continuation I/O
    

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18. Logic
    Effects
    Monadic I/O
    Stream I/O
    Continuation I/O
    

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19. Logic
    Effects
    Monadic I/O
    

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24. Program
    Compiler, binary
    

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25. Logic
    Effects
    Stream I/O
    

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26. Program
    binary
    Operating
    System
    

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27. Program
    binary
    Operating
    System
    Requests
    "Write" msgs
    

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28. Program
    binary
    Operating
    System
    Requests
    Responses
    "Write" msgs
    "Read" msgs
    

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38. Program
    binary
    Operating
    System
    Requests
    Responses
    "Write" msgs
    "Read" msgs
    

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42. Reactive system
    versus
    
    Transformational system
    

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43. "A transformational system repeatedly waits for
    all its inputs to arrive, carries out some
    processing, and outputs the results when the
    processing is done."
    (1998)
    

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44. (start)

    Inputs
    Processing
    Output

    (done)
    

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45. Examples:

    

    Compiler

    UNIX commands
    

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46. "A reactive system continuously interacts with
    its environment, using inputs and outputs that
    are either continuous in time or discrete. The
    inputs and outputs are often asynchronous,
    meaning that they may arrive or change values
    unpredictably at any point in time."
    

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47. Input
    Processing
    Output
    

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48. Examples:

    

    Real-time systems
    User interfaces
    Websites
    Servers
    

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49. 1990
    Reactive programs
    Transformational programs
    2000 2010
    

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50. 1990
    Pascal
    FORTRAN
    BASIC
    C
    Reactive programs
    Transformational programs
    2000 2010
    Java
    JavaScript
    

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53. 1990
    Pascal
    FORTRAN
    BASIC
    C
    Reactive programs
    Transformational programs
    2000 2010
    Java
    JavaScript
    Haskell

    Stream I/O
    

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54. 1990
    Pascal
    FORTRAN
    BASIC
    C
    Reactive programs
    Transformational programs
    2000 2010
    Java
    JavaScript
    Monadic I/O good for 

    transformational programs
    
    

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55. 1990
    Pascal
    FORTRAN
    BASIC
    C
    Reactive programs
    Transformational programs
    2000 2010
    Java
    JavaScript
    Haskell

    Monadic I/O
    

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56. 1990
    Pascal
    FORTRAN
    BASIC
    C
    Reactive programs
    Transformational programs
    2000 2010
    Java
    JavaScript
    Multimedia
    

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57. 1990
    Pascal
    FORTRAN
    BASIC
    C
    Reactive programs
    Transformational programs
    2000 2010
    Java
    JavaScript
    Period of
    confusion
    

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58. 1990
    Pascal
    FORTRAN
    BASIC
    C
    Reactive programs
    Transformational programs
    2000 2010
    Java
    JavaScript
    Period of
    confusion
    

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59. 1990
    Pascal
    FORTRAN
    BASIC
    C
    Reactive programs
    Transformational programs
    2000 2010
    Java
    JavaScript
    Shared-memory
    concurrency
    

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60. 1990
    Pascal
    FORTRAN
    BASIC
    C
    Reactive programs
    Transformational programs
    2000 2010
    Java
    JavaScript
    Shared-memory
    concurrency
    

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61. 1990
    Pascal
    FORTRAN
    BASIC
    C
    Reactive programs
    Transformational programs
    2000 2010
    Java
    JavaScript
    Early JavaScript

    apps
    

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62. 1990
    Pascal
    FORTRAN
    BASIC
    C
    Reactive programs
    Transformational programs
    2000 2010
    Java
    JavaScript
    Early JavaScript

    apps
    

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63. 1990
    Pascal
    FORTRAN
    BASIC
    C
    Reactive programs
    Transformational programs
    2000 2010
    Java
    JavaScript
    

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64. 1990
    Pascal
    FORTRAN
    BASIC
    C
    Reactive programs
    Transformational programs
    2000 2010
    Java
    JavaScript
    Asynchronous
    
    Continuous interaction
    

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65. 1990
    Pascal
    FORTRAN
    BASIC
    C
    Reactive programs
    Transformational programs
    2000 2010
    Java
    JavaScript
    Asynchronous
    
    Continuous interaction
    

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66. 1990
    Pascal
    FORTRAN
    BASIC
    C
    Reactive programs
    Transformational programs
    2000 2010
    Java
    JavaScript
    Message passing

    concurrency
    

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67. Program
    binary
    Operating
    System
    Requests
    Responses
    Stream I/O
    Message passing
    Lazy lists

    Blocking
    

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68. Program
    binary
    Operating
    System
    Requests
    Responses
    "Stream I/O"
    Message passing
    Lazy lists Streams

    Blocking Asynchronous
    

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69. Program
    binary
    Operating
    System
    Requests
    Responses
    Message passing
    Streams

    Asynchronous
    Cycle.js
    

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86. Stream of DOM events
    Stream of actions
    Stream of state
    Stream of reducers
    Stream of markup to the DOM
    

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87. Asynchronous message passing
    User interfaces or any reactive system
    Separation of concerns

    Handling question-and-answer I/O
    Cycle.js
    

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93. Elm
    

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95. Elm
    program
    Elm
    runtime
    Task
    Result
    "Do this and then 

    that and tell me the

    result"
    

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101. Monadic I/O
     

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103. Task: Monadic I/O
     Msg and Cmd: "Stream I/O"
     Elm
     

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104. Transformational 

     subprogram with Monadic I/O
     Reactive program

     with "Stream I/O"
     Elm
     

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105. Store Components
     State
     Action
     Flux
     

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106. Message passing

     +

     purely functional

     =

     "Stream I/O"?
     

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107. 1990
     Reactive programs
     Transformational programs
     2000 2010
     

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108. 1990
     Pascal
     FORTRAN
     BASIC
     C
     Reactive programs
     Transformational programs
     2000 2010
     

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109. 1990
     Pascal
     FORTRAN
     BASIC
     C
     Reactive programs
     Transformational programs
     2000 2010
     

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110. 1990
     Pascal
     FORTRAN
     BASIC
     Java
     JavaScript
     Ruby
     C#
     C
     Reactive programs
     Transformational programs
     2000 2010
     

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111. 1990
     Pascal
     FORTRAN
     BASIC
     Java
     JavaScript
     Ruby
     C#
     C
     Reactive programs
     Transformational programs
     2000 2010
     

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112. 1990
     Pascal
     FORTRAN
     BASIC
     Java
     JavaScript
     Ruby
     C#
     C
     Reactive programs
     Transformational programs
     2000 2010
     Elm
     Elixir
     Clojure
     Dart
     

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113. 1990
     Pascal
     FORTRAN
     BASIC
     Java
     JavaScript
     Ruby
     C#
     C
     Reactive programs
     Transformational programs
     2000 2010
     Elm
     Elixir
     Clojure
     Dart
     Asynchronous
     Message passing
     Event-driven
     

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114. Framework Concurrency
     Cycle.js Message passing
     React / Redux Message passing
     Elm Message passing
     Vue.js (Vuex) Message passing
     Angular v1 ($scope) Shared-memory
     ngrx Message passing
     

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115. Framework Paradigm
     Cycle.js Wannabe functional
     React / Redux Wannabe functional
     Elm Functional
     Vue.js (Vuex) OOP
     Angular v1 ($scope) OOP
     ngrx Wannabe functional
     

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116. The future is
     functional, event-driven
     message passing concurrent
     programming
     

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117. Thank you 

     #
     

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