Hi Simon,
I am just starting the proposal: gathering interested parties and pointers
to related information.
Thanks for the pointer to Typed Template Haskell. I was actually unaware of
the extent to which Typed Template Haskell is restricted. I have not seen
any usage of Typed Template Haskell in the wild or been able to use it
myself unfortunately due to backwards compatibility needs (once the next
GHC release is out libraries will start to consider dropping 7.6 support
and we will see more usage, although Ubuntu still ships 7.6 by default).
I will study Typed Template Haskell.
Greg Weber
On Mon, Feb 2, 2015 at 9:33 AM, Simon Peyton Jones
The new TH is already split into two parts https://ghc.haskell.org/trac/ghc/blog/Template%20Haskell%20Proposal as I’m sure you know
· Typed TH is for expressions only, and doesn’t have reify, nor any Q monad.
· Untyped TH is the wild west
Typed TH may get some of what you want? Certainly you want to acknowledge the existing split in your own design.
The proposal could do with examples to illustrate what the difficulties are. What bad things happen in the Q monad? Can you give examples of reasoning that would be valid in level 1 but not in level 2. etc. More precision please!
Simon
*From:* Glasgow-haskell-users [mailto: glasgow-haskell-users-bounces@haskell.org] *On Behalf Of *Greg Weber *Sent:* 30 January 2015 23:39 *To:* ghc-devs@haskell.org; GHC users *Cc:* David Terei; Maxwell Swadling *Subject:* Restricted Template Haskell
Hello GHC friends!
I am starting up a proposal for variants of Template Haskell that restrict what operations are available. The goal is to make TH easier for users to reason about and to allow for an easier compilation story.
Here is the proposal page:
https://ghc.haskell.org/trac/ghc/wiki/TemplateHaskell/Restricted
Right now the proposal does not have any details and the goal is to write out a clear specification.
If this sounds interesting to you, let me know or leave some feedback on the wiki.
Thanks,
Greg Weber