Duane, the dictionary has string keys; its values are just values of a union type--they are not modules in themselves, but just tags that the case statement can key on in order to decide on which module to send the message to.
On the second point, the top-level component knows enough about the incoming message to get the value from the message_type key. The type of the data field is opaque to the top-level; the top-level just sees it as Json.Value. This does in fact work; it's just hard to test. On Fri, Jul 29, 2016 at 3:47 PM, Duane Johnson <[email protected]> wrote: > > On Fri, Jul 29, 2016 at 12:52 PM, Paul Blair <[email protected]> wrote: > >> toMessage : FromServer -> Message >> toMessage incoming = >> case Dict.get incoming.message_type componentDictionary of >> Just MyInnerComponent -> >> InnerComponentModule.toMessage incoming |> >> MyInnerComponentMessageWrapper >> Nothing -> >> ... >> > > > I'm still learning Elm, so forgive that this is not necessarily going to > be expert advice :) > > My first question is, what is the type of `componentDictionary`? It looks > to me like it has `String` type keys, but then I don't understand what the > type signature of the value is. `Maybe type`? How can you match on `Just > MyInnerComponent`? > > Second question: it seems like the top-level component *must* know > something about the messages in order to route to subcomponents. Can you > include a list of json keys in that routing information, so that you can > pass a narrower scope of data into each subcomponent? It seems like if you > can, that would make your testing story a lot easier. > > Duane > > -- > You received this message because you are subscribed to a topic in the > Google Groups "Elm Discuss" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/elm-discuss/fwDl6deEC1Q/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Elm Discuss" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
