Problems.P07

Description

Part of Ninety-Nine Haskell Problems. Some solutions are in Solutions.P07.

Synopsis

Documentation

Transform a list, possibly holding lists as elements, into a "flat" list by replacing each list with its elements recursively.

>>> flatten $ Elem 5
[5]

>>> flatten $ List [Elem 1, List [Elem 2, List [Elem 3, Elem 4], Elem 5]]
[1,2,3,4,5]

>>> flatten $ List []
[]

A list type with arbitrary nesting of lists.

Constructors

Elem a	A non-list element.
List [NestedList a]	Nested list.

Instances details

Generic (NestedList a) Source #
Instance details Defined in Problems.Lists Associated Types type Rep (NestedList a) :: Type -> Type # Methods from :: NestedList a -> Rep (NestedList a) x # to :: Rep (NestedList a) x -> NestedList a #
Show a => Show (NestedList a) Source #
Instance details Defined in Problems.Lists Methods showsPrec :: Int -> NestedList a -> ShowS # show :: NestedList a -> String # showList :: [NestedList a] -> ShowS #
Eq a => Eq (NestedList a) Source #
Instance details Defined in Problems.Lists Methods (==) :: NestedList a -> NestedList a -> Bool # (/=) :: NestedList a -> NestedList a -> Bool #
type Rep (NestedList a) Source #
Instance details Defined in Problems.Lists type Rep (NestedList a) = D1 ('MetaData "NestedList" "Problems.Lists" "ninetynine-1.3.0-4Xxr3hBGtJH9Ff8qb2Invo" 'False) (C1 ('MetaCons "Elem" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 a)) :+: C1 ('MetaCons "List" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 [NestedList a])))