diff options
Diffstat (limited to 'libraries/base/Data/Void.hs')
| -rw-r--r-- | libraries/base/Data/Void.hs | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/libraries/base/Data/Void.hs b/libraries/base/Data/Void.hs index beb6041f62..5c2886889b 100644 --- a/libraries/base/Data/Void.hs +++ b/libraries/base/Data/Void.hs @@ -79,6 +79,16 @@ absurd a = case a of {} -- | If 'Void' is uninhabited then any 'Functor' that holds only -- values of type 'Void' is holding no values. -- +-- Using @ApplicativeDo@: \'@'vacuous' theVoid@\' can be understood as the +-- @do@ expression +-- +-- @ +-- do void <- theVoid +-- pure (absurd void) +-- @ +-- +-- with an inferred @Functor@ constraint. +-- -- @since 4.8.0.0 vacuous :: Functor f => f Void -> f a vacuous = fmap absurd |