I thought of a potential advantage of keeping the behavior as it currently
is: it gives library authors a way of making record types opaque.
Consider a union type.
type Foo = FooA Float | FooB Int | FooC
>
If an author wants the type constructors as part of the public API, their
module header looks like this:
module FooModule exposing (Foo(..))
>
But if they wants to hide the type constructors, they can change it to this:
module FooModule exposing (Foo)
>
A record type always exposes its definition & constructors:
module FooModule exposing (PublicFoo)
> type alias PublicFoo = { a : Float }
>
But using the behavior that Peter asks about, an author can alias the
record and hide its "record-ness" from library users:
module FooModule exposing (PublicFoo)
>
type alias PublicFoo = PrivateFoo
>
type alias PrivateFoo = { a : Float }
>
On Wed, Jun 22, 2016 at 11:17 PM, Peter Damoc <[email protected]> wrote:
> Alex, your use-case is way more interesting and useful than mine.
>
> What I was trying to do was more like a simple rename.
> I put the MainModel in a different file because it needed to be imported
> in different places and I ended up with a circular dependency but I wanted
> to keep referring to it as Model in the original location.
>
>
>
> On Wed, Jun 22, 2016 at 11:57 PM, Alex Lew <[email protected]> wrote:
>
>> This would be useful to have, especially if it worked on type aliases
>> with type arguments:
>>
>> type alias Container a = { contents : a }
>> type alias IntContainer = Container Int
>>
>> myContainer = IntContainer 3
>>
>> -- Or even this, which would require some decisions about how what order
>> the
>> -- record fields of `Managed Book` would be in.
>> type alias Managed a = { a | managerId : Int }
>> type alias Book = { title : String, author : String }
>> type alias ManagedBook = Managed Book
>>
>> harryPotter = ManagedBook 50321 "Harry Potter" "JK Rowling"
>>
>>
>> On Wednesday, June 22, 2016 at 4:05:04 AM UTC-4, Peter Damoc wrote:
>>>
>>> This does not work:
>>>
>>> type alias MainModel = { int : Int}
>>>
>>> type alias Model = MainModel
>>>
>>> init = Model 1
>>>
>>> and I'm wondering if this is a bug or the expected behavior.
>>>
>>>
>>>
>>>
>>>
>>>
>>> --
>>> There is NO FATE, we are the creators.
>>> blog: http://damoc.ro/
>>>
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>>
>
>
>
> --
> There is NO FATE, we are the creators.
> blog: http://damoc.ro/
>
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