Data.Sequence.NonEmpty

data Seq a

A sequence which is guaranteed to contain at least one element.

Constructors

• Seq a (Seq a)

Instances

• (Show a) => Show (Seq a)
• (Eq a) => Eq (Seq a)
• (Ord a) => Ord (Seq a)
• Functor Seq
• Apply Seq
• Applicative Seq
• Bind Seq
• Monad Seq
• Semigroup (Seq a)
• Alt Seq
• Foldable Seq
• Foldable1 Seq
• Traversable Seq
• Unfoldable1 Seq

singleton :: forall a. a -> Seq a

O(1). Construct a sequence from a single element.

cons :: forall a. a -> Seq a -> Seq a

O(1). Add an element to the left end of a sequence.

snoc :: forall a. Seq a -> a -> Seq a

O(1). Add an element to the right end of a sequence.

append :: forall a. Seq a -> Seq a -> Seq a

O(log(min(i,n-i))). Join two sequence values together.

fromFoldable1 :: forall f. Foldable1 f => f ~> Seq

Probably O(n), but depends on the Foldable1 instance. Unfold a non-empty sequence from any Foldable1.

Note that we cannot provide a fromFoldable, because the argument could be empty.

length :: forall a. Seq a -> Int

O(1). The number of elements in the sequence.

inBounds :: forall a. Int -> Seq a -> Boolean

O(1). True if the given index specifies an element that exists in the sequence, false otherwise.

uncons :: forall a. Seq a -> Tuple a (Seq a)

O(1). Take one element off the left side of a Seq and return it, together with the (possibly empty) remainder of the Seq.

unsnoc :: forall a. Seq a -> Tuple (Seq a) a

O(1). Take one element off the right side of a Seq and return it, together with the (possibly empty) remainder of the Seq.

head :: forall a. Seq a -> a

O(1). Get the first element of a non-empty sequence. Equivalent to index 0.

tail :: forall a. Seq a -> Seq a

O(1). Get all but the first element of a non-empty sequence. The returned sequence is possibly empty. Equivalent to drop 1.

init :: forall a. Seq a -> Seq a

O(1). Get all but the last element of a non-empty sequence. Possibly empty.

last :: forall a. Seq a -> a

O(1). Get the last element of a non-empty sequence.

toUnfoldable :: forall f. Functor f => Unfoldable f => Seq ~> f

Probably O(n), but depends on the Unfoldable instance. Turn a Seq into any Unfoldable.

toUnfoldable1 :: forall f. Functor f => Unfoldable1 f => Seq ~> f

Probably O(n), but depends on the Unfoldable instance. Turn a Seq into any Unfoldable1.

toPlain :: Seq ~> Seq

O(1). Turn a non-empty sequence into a "plain" sequence (i.e. one from Data.Sequence), containing the same elements.

splitAt :: forall a. Int -> Seq a -> Tuple (Seq a) (Seq a)

O(log(min(i,n-i))). Split the sequence into two (possibly empty) subsequences. The first subsequence will have i elements (unless there are not that many in the whole sequence, in which case the first element is the same sequence, unchanged).

take :: forall a. Int -> Seq a -> Seq a

O(log(min(i,n-i))). Take a certain number of values from the left end of a sequence, and discard the rest, returning a possibly empty sequence.

drop :: forall a. Int -> Seq a -> Seq a

O(log(min(i,n-i))). Discard a given number of elements from the left end of a sequence, returning a possibly empty sequence.

filter :: forall a. (a -> Boolean) -> Seq a -> Seq a

O(n). Create a new (possibly empty) sequence which contains only those elements of the input sequence which satisfy the given predicate.

index :: forall a. Int -> Seq a -> Maybe a

O(log(min(i,n-i))). Retrieve the element at the given index in the sequence. This function is zero-based; that is, the first element in a sequence xs can be retrieved with index 0 xs.

adjust :: forall a. (a -> a) -> Int -> Seq a -> Seq a

O(log(min(i,n-i))). Adjust the element at the specified index by applying the given function to it. If the index is out of range, the sequence is returned unchanged.

replace :: forall a. a -> Int -> Seq a -> Seq a

O(log(min(i,n-i))). Replace the element at the specified index with a new element. If the index is out of range, the sequence is returned unchanged.