Very tentatively, this might be a bug. I would think that because 
*model_page* is not capitalized, it should be interpreted as a value, not a 
module. That should resolve to a record that you can access a field on. I 
think your code can be unambiguously parsed.

(Where you might get into trouble is if module Foo defines a record type 
alias Bar, and there's also a module Foo.Bar. Though I still think that 
works because these are functions, not records, and you can't call a module 
name.)

On Thursday, January 12, 2017 at 4:12:29 PM UTC-8, Brian Marick wrote:
>
> Short: I am getting this error when `model_page` is a record inside module 
> `Animals.Model`
>
> Cannot find variable `Model.model_page.set`.
>
> 13|       model |> Model.model_page.set (Page.fromLocation location) |> 
> noCmd
>                          ^^^^^^^^^^^^^^
> No module called `Model.model_page` has been imported. 
>
>
> The relevant import statement is:
>
> import Animals.Model as Model exposing (..)
>
>
> How do I tell the compiler that `Model` contains a record with a `set` 
> field, rather than that `Model.model_page` is a module with a top-level 
> definition named `set`?
> ---------------
> ---------------
>
> I’m using Monocle 
> http://package.elm-lang.org/packages/arturopala/elm-monocle/latest for 
> lenses with good success. It allows a reasonable approximation to the sort 
> of deep accessors and “setters” that are easier in dynamically typed 
> languages. For example, in Clojure, you can traverse a record with `(
> get-in record [:profile :name])
>
> What a lens library allows is a record with `get` and `set` functions that 
> work on a possibly-nested “part” of a larger whole. 
>
> Because I’m obsessive about naming, I’ve being experimenting with how to 
> make lenses available to client code. I previously slopped them all into a 
> giant `Lenses.elm` namespace that was imported like this:
>
> import Animals.Animal.Lenses exposing (..)
>
>
> But I’d rather include the lens definitions alongside the `type alias` 
> declarations that they apply to. That is:
>
> type alias Model = 
>   { page : Page.PageChoice
>
> …
>
> -- Boilerplate Lenses
>       
> model_page : UpdatingLens Model Page.PageChoice
> model_page = lens .page (\ p w -> { w | page = p })
>
>
> My goal is to stop using “import Animals.Animal.Lenses exposing (..)”. 
> Instead, I’d have more specific imports and use qualified names like 
> `Model.pageLens`. That is, instead of an implicit reference to the kind of 
> the data the lens manipulates (“model_”), it’d be encoded in the module 
> name as a convention I’d follow (“Model.*lens”). 
>
> But the compiler error above is getting in my way.
>
> For reference: 
> - the lens definitions 
> https://github.com/marick/eecrit/blob/621466af5e4c5f46595c903b28bd3cca91995586/web/elm/Animals/Animal/Lenses.elm
> - the use: 
> https://github.com/marick/eecrit/blob/621466af5e4c5f46595c903b28bd3cca91995586/web/elm/Animals/Pages/Update.elm#L13
>
>

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