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arowM/Default.elm

Last active November 29, 2017 08:14
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Revisions

  1. arowM revised this gist Nov 29, 2017. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion Default.elm
    View file
    Original file line number Diff line number Diff line change
    @@ -28,7 +28,7 @@ default (Default a) =

    {-|
    ```
    instance (Default Int) where
    instance Default Int where
    default :: Int
    default = 0
    ```
  2. arowM revised this gist Nov 29, 2017. 1 changed file with 11 additions and 0 deletions.
    11 changes: 11 additions & 0 deletions Default.elm
    View file
    Original file line number Diff line number Diff line change
    @@ -12,6 +12,10 @@ import Task exposing (Task)


    {-| Phantom type to define default value of type `a`.
    ```
    class Default a where
    default :: a
    ```
    -}
    type Default a
    = Default a
    @@ -22,6 +26,13 @@ default (Default a) =
    a


    {-|
    ```
    instance (Default Int) where
    default :: Int
    default = 0
    ```
    -}
    int : Default Int
    int =
    Default 0
  3. arowM revised this gist Nov 29, 2017. 1 changed file with 0 additions and 2 deletions.
    2 changes: 0 additions & 2 deletions Default.elm
    View file
    Original file line number Diff line number Diff line change
    @@ -38,8 +38,6 @@ maybe (Default a) =


    {-| A Stub.
    import Task
    stubTask int (Task.succeed 10)
    --> 0
  4. arowM created this gist Nov 29, 2017.
    57 changes: 57 additions & 0 deletions Default.elm
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,57 @@
    module Default
    exposing
    ( Default
    , default
    , int
    , string
    , maybe
    , stubTask
    )

    import Task exposing (Task)


    {-| Phantom type to define default value of type `a`.
    -}
    type Default a
    = Default a


    default : Default a -> a
    default (Default a) =
    a


    int : Default Int
    int =
    Default 0


    string : Default String
    string =
    Default ""


    maybe : Default a -> Default (Maybe a)
    maybe (Default a) =
    Default <| Just a


    {-| A Stub.
    import Task
    stubTask int (Task.succeed 10)
    --> 0
    stubTask string (Task.succeed "foo")
    --> ""
    stubTask (maybe string) (Task.succeed <| Nothing)
    --> Just ""
    stubTask (maybe (maybe int)) (Task.succeed <| Just (Just 3))
    --> Just (Just 0)
    -}
    stubTask : Default a -> Task error a -> a
    stubTask def _ =
    default def