Chaining type providers

Question

I am wondering if it is possible to create an XmlProvider from the data provided by an SqlDataProvider.

Naively it would be something like this:

type sql = SqlDataProvider<...>

let xml =
    query {
      for item in sql.GetDataContext().Main.Items do
      select item.XmlData
      head
    }

type xmlType = XmlProvider<xml>

Of course this fails because xml is not a literal.

I'm curious if this is possible.

Helge Rene Urholm Helge Rene Urholm · Accepted Answer · 2017-01-10T21:18:29

The short answer is: Yes.

And then the ifs and buts:

Given that the returned xml is structured (as in: about equal each time) then providing an example which is a literal would be ok.

Then the data from the database could be parsed like:

let someXmlDataNowType = xmlType.Parse(xml)

This is probably not what you want or asked about, but then again the short answer is: No ;-)

If you have a lot of queries with different XML my take would have been to write some code to generate the different XML in some files and even possibly write the f# automagically...

Chaining type providers

1 Answers