tobz619

4 ms·

1. 1.▲
   by tobz619 2y ago

   There's a difference between empty strings and Null values imo. Just "" != Nothing If you want to handle empty strings as a input in haskell then you have a function of type `f :: String -> b` and you pattern match on your
2. 2.▲
   by tobz619 2y ago

   Haskell also has GADTs: https://ghc.gitlab.haskell.org/ghc/doc/users_guide/exts/gadt... , firstly as an extension and now it's built into the latest version of this year's compiler
3. 3.▲
   by tobz619 2y ago

   It can using pure or return or if working with just Maybe specifically then Maybe is defined like so: data Maybe a = Just a | Nothing So to make an X a Maybe X, you'd put a Just before a value of type X. For example: one :: Int one = 1
4. 4.▲
   by tobz619 2y ago

   If you have a value "aValue :: a" and a monadic function of "mFunc :: (a -> Maybe b)" that's essentially just asking you to use `>>= :: Maybe a -> (a -> Maybe b) -> Maybe b` as well as `pure :: App