Saturday, September 24, 2011

Const value and F# Type Provider parameter

I guess i forget to put in a sample to show how to declare a constant in F#.

Now I found a way to use this feature with TypeProviders. The type provider is the newly introduced feature in  F#, but it has a major drawback: cannot have variable in the type declaration. When I wrote Regex Type Provider, I know why should be like this way and it is not easy to fix it. In the meanwhile, this bothers me a lot. Today at least I find a way to give a little bit more flexibility by using a const.

[ < Literal > ]
let conStr = "< my con string> "

type T = Microsoft.FSharp.Data.TypeProviders.SqlDataConnection ( constr )
let db = T.GetDataContext()

This enable me to use conditional compilation to target different database. At least a little more freedom than before.

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