diff options
Diffstat (limited to 'FunctorToMaybe.hs')
| -rw-r--r-- | FunctorToMaybe.hs | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/FunctorToMaybe.hs b/FunctorToMaybe.hs index 0fd6b7f..a718010 100644 --- a/FunctorToMaybe.hs +++ b/FunctorToMaybe.hs | |||
| @@ -18,8 +18,13 @@ | |||
| 18 | -- implemented the 'FunctorToMaybe' type class, then 'functorToEither' could be used to | 18 | -- implemented the 'FunctorToMaybe' type class, then 'functorToEither' could be used to |
| 19 | -- seperate the noise from the work-product. | 19 | -- seperate the noise from the work-product. |
| 20 | -- | 20 | -- |
| 21 | {-# LANGUAGE CPP #-} | ||
| 21 | module FunctorToMaybe where | 22 | module FunctorToMaybe where |
| 22 | 23 | ||
| 24 | #if MIN_VERSION_base(4,6,0) | ||
| 25 | #else | ||
| 26 | import Control.Monad.Instances | ||
| 27 | #endif | ||
| 23 | 28 | ||
| 24 | -- | The 'FunctorToMaybe' class genaralizes 'Maybe' in that the | 29 | -- | The 'FunctorToMaybe' class genaralizes 'Maybe' in that the |
| 25 | -- there may be multiple null elements. | 30 | -- there may be multiple null elements. |