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An unofficial issue tracker for all things Haskell-related
https://github.com/ekmett/lens/pull/732 remains unresolved. The next step would be to implement tests using https://www.reddit.com/r/haskell/comments/69ots1/notorious_lens_errors_thread/.
Right now the most common way to construct a `Numeric.Natural` is by using `fromInteger` directly or indirectly (like through round or a numeric literal). This is kind of ridiculous, because...
Because as far as I can see it is safe but requires partial functions to implement: ``` type Pair a a = Pair a a deriving Functor zipWith :: Distributive...
The obvious instance obeys all of the laws so this should be a thing.
``` caseMay x of A -> a B -> b ``` would be desugared to ``` case x of A -> Just a B -> Just b _ -> Nothing...
* Emphasize in which cases the function will result in an error. * Point at total alternatives, e.g. `head`'s documentation should mention `listToMaybe`.
When I build packages that depend on haskell-src-exts it often seems that the build of haskell-src-exts only starts once most other dependencies have finished. Then CPU utilization drops while everything...
`atomicModifyIORef :: IORef a -> (a -> (a, b)) -> IO b` into `atomicModifyIORefM :: MonadIO m => IORef a -> (a -> m (b, a)) -> m b` and...
This would allow people to define lens-style `Fold`s, `Prism`s and `Iso`s without depending on lens.
I seem to be using this so often I can only attribute it to that phenomenon where after you just learned something you start seeing it everywhere. For example: ```...