Since prints :: Cake -> String
and flavors :: [Cake]
, we know
map prints flavors :: [String]
But this doesn't jive with the context in which it is used, since in
" " ++ expr
the " "
is clearly a String
and we therefore expect expr
to be a String
and not a [String]
.
To fix this, you should write or find a function which converts your [String]
into a String
in some way -- there are many candidate behaviors for this type, so you should decide what behavior you want and then find a way to achieve that behavior.
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