Forgot to CC the list:
I'd be -1 on an operator, I think having a named function for this is a
good thing for readability of code.
As far as good style: I personally think it is. In classy-prelude, I
actually export the Foldable-based `mapM` by default, and will regularly
use that (or forM) for this kind of code.
On Tue, Sep 23, 2014 at 8:27 AM, Kazu Yamamoto
Hi,
Recently, I need to write the following code:
getModTime :: Maybe FilePath -> IO (Maybe UTCTime) getModTime mfile = case mfile of Nothing -> return Nothing Just file -> Just <$> getModificationTime file
I feel that this is redundant. So, I used 'traverse' instead:
getModTime :: Maybe FilePath -> IO (Maybe UTCTime) getModTime mfile = getModificationTime `traverse` mfile
First, I would like to know whether or not this is a good coding style.
Second, if this is acceptable, why don't we define an operator? For instance,
(<:>) :: (Traversable t, Applicative f) => (a -> f b) -> t a -> f (t b) (<:>) = traverse
getModTime :: Maybe FilePath -> IO (Maybe UTCTime) getModTime mfile = getModificationTime <:> mfile
Is there such an operator already?
Regards,
--Kazu _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe