Support for generating Template Haskell code

[wavewave]

I am wondering whether generating TH code (splice expression) is possible in current implementation, and if not, is the support for TH planned? Thanks!

[judah]

Thanks for the feature request! We don't have combinators for splices, but at first glance they look pretty reasonable to add to our API.

Out of curiosity, what is your intended use of them? In my use in the past I've been doing all of the codegen with ghc-source-gen itself, so there was no need for TH's codegen. But I can see how this would be useful to interact with another library that already provides a TH API.

[wavewave]

Thank you for considering the addition!

My use case is to autogenerate of Haskell code for binding to C++ template code. C++ part is wrapped as C macro, and the TH haskell code is generating a name for FFI function. In that case, at the code gen time, there is no way to know the FFI function name, i.e. template instantiation time is after code generation. Therefore, supporting code generation of TH code is needed. (meta-meta-programming :-) )
Here is where I implemented it:
https://github.com/wavewave/fficxx/blob/21487f389b9f88cad6f506fb0db06534ed96bc28/fficxx/lib/FFICXX/Generate/Code/HsTemplate.hs#L65-L86
and here is where I need a combinator for TH.
https://github.com/wavewave/fficxx/blob/21487f389b9f88cad6f506fb0db06534ed96bc28/fficxx/lib/FFICXX/Generate/Code/Primitive.hs#L756
Thank you for your great library!