TypeLits question, how to build a Type Application with Symbol index

[Gabor Greif]

Hello devs,

I have

{{{
data D (n :: Symbol)
}}}

in my module, and I want to obtain a type

{{{
D "YAY!"
}}}

programmatically. Where can I find code that performs this (or
something similar)?

1) I have to look up |D| in the current TyEnv (what if it is in a
specific module?),
2) I have to build the type index (of kind Symbol), this involves
FastString, looks non-trivial,
3) Apply 1) on 2), this is easy.

Any hints welcome!

Thanks and cheers,

    Gabor


PS: some morsels I have so far:

for 1)
compiler/prelude/PrelNames.lhs:gHC_GENERICS    = mkBaseModule (fsLit
"GHC.Generics")