ElixirRuhr.001: Good Tooling educates

Where are we in Elixir right now and what are the challenges faced by both newcomers and tool designers? This talk tries to answer these questions and advocates taking humans into account when designing even the nerdiest software tools.

Transcript

1. Good Tooling Educates
   René Föhring // @rrrene
   

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2. @rrrene
   

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3. @rrrene
   (read in pirate voice)
   

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4. @rrrene
   (read in pirate voice)
   coding @ .
   teacher ∙ researcher
   (insert more self-description here)
   

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5. @rrrene
   creator of Credo
   running ElixirStatus / Inch CI
   

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6. Where are we now?
   

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7. Elixir’s recent rise from “totally unknown” to
   “still definitely unknown but mentioned in
   hushed tones” [...]
   Clark Kampfe in “Elixir is not Ruby”
   https://zeroclarkthirty.com/2015-11-01-elixir-is-not-ruby.html
   

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8. What‘s the „newcomer experience“ like?
   

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9. GREAT FOUNDATION
   elixirc
   mix
   Hex
   Ecto
   Phoenix
   

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10. GREAT FOUNDATION
    elixirc
    mix
    Hex
    Ecto
    Phoenix
    is Rails 5
    https://medium.com/infinite-red/phoenix-is-rails-5-f6d28e57395
    

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11. Markdown parser: yes
    HTML Sanitizer: no
    

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12. Talk is cheap, contribution is king!
    

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15. (╯°□°)╯︵ ┻━┻
    It’s the same!
    

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16. 1 def get_item_if_member(filenames, item) do
    2 if Enum.member?(filenames,
    _____"/home/rene/projects/credo/lib/credo.ex") do
    3 item
    4 |> IO.inspect
    5 end
    6 end
    

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17. 1 def get_item_if_member(filenames, item) do
    2 if Enum.member?(filenames,
    _____"/home/rene/projects/credo/lib/credo.ex") do
    3 item
    4 |> IO.inspect
    5 end
    6 end
    

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18. 1 def get_item_if_member(filenames, item) do
    2 if Enum.member?(filenames,
    _____"/home/rene/projects/credo/lib/credo.ex") do
    3 item
    4 |> IO.inspect
    5 end
    6 end
    

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19. SEMANTIC CATEGORIES
    readability
    software design
    refactoring opportunities
    consistency
    warnings
    

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20. 1 defmodule ElixirRuhr do
    2 @github_url "https://github.com/"
    3 end
    4
    5 defmodule ElixirRuhr2 do
    6 @githubURL "https://github.com/"
    7 end
    

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21. DYNAMIC PRIORITIES
    higher
    high
    normal
    low
    ignore
    

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22. issues ordered by priority
    20
    12
    11
    6
    5
    1
    -1
    -2
    -2
    -10
    -11
    -100
    

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23. issues ordered by priority
    20
    12
    11
    6
    5
    1
    -1
    -2
    -2
    -10
    -11
    -100
    (normal)
    

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24. issues ordered by priority
    20
    12
    11
    6
    5
    1
    -1
    -2
    -2
    -10
    -11
    -100
    (strict)
    

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25. Consistency Checks
    

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26. # preferred way - common suffix Error
    defmodule BadHTTPHeaderError do
    defexception [:message]
    end
    defmodule UserRequestError do
    defexception [:message]
    end
    

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27. # also okay - common suffix Exception
    defmodule BadHTTPHeaderException do
    defexception [:message]
    end
    defmodule UserRequestException do
    defexception [:message]
    end
    

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28. # also okay - consistent *prefix* Invalid
    defmodule InvalidHTTPHeader do
    defexception [:message]
    end
    defmodule InvalidUserRequest do
    defexception [:message]
    end
    

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29. # bad
    # there is no common naming scheme for exceptions
    defmodule InvalidHeader do
    defexception [:message]
    end
    defmodule UserRequestFailed do
    defexception [:message]
    end
    

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33. END-OF-TALK
    # Credo – Static code analysis
    https://github.com/rrrene/credo
    # Bunt – 256 colors for your CLI
    https://github.com/rrrene/bunt
    # @rrrene‘s personal blog
    http://trivelop.de
    

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