Good to see you around, Sandy!
> On Mar 18, 2020, at 6:54 PM, Sandy Maguire <sa...@sandymaguire.me> wrote:
>
> I mean if `insert :: a -> Container a -> Container a`, and I call it with
> `[e| insert 5 True |]`, the quote will fail.
I don't observe this. Specifically, when I compile
> {-# LANGUAGE TemplateHaskellQuotes #-}
>
> module Bug where
>
> import Prelude ( Bool(..), undefined )
>
> data Container a
>
> insert :: a -> Container a -> Container a
> insert = undefined
>
> quote = [e| insert 5 True |]
GHC happily succeeds.
I think what you want, though, is reasonable: you want the ability to send an
expression through GHC's type-checker. I think we'd need to extend TH to be
able to support this, and it will be hard to come up with a good design, I
think. (Specifically, I'm worried about interactions with top-level defined
entities, whose types might not really be known by the time of splice
processing.) This might all be worthwhile -- singletons would be able to be
improved with this, for example -- but it's not cheap, sadly.
Richard_______________________________________________
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