Data.DString

Difference strings: a data structure for O(1) append on strings. Note that a DString is just a newtype wrapper around a 'DList Char'. The reason we need a new type instead of just a type synonym is that we can have an 'instance IsString DString' so we can write overloaded string literals of type DString.

Documentation

data DString

Instances

IsString DString

Monoid DString

Conversion

fromDList :: DList Char -> DString

Convert a difference list of Chars to a difference string

toDList :: DString -> DList Char

Convert a difference string to a difference list

toString :: DString -> String

Convert a difference string back to a normal String

fromShowS :: ShowS -> DString

Convert a ShowS to a difference string

toShowS :: DString -> ShowS

Convert a difference string to a ShowS

Basic functions

empty :: DString

Create a difference string containing no characters

singleton :: Char -> DString

Build a difference string from a single Char

cons :: Char -> DString -> DString

O(1), Prepend a Char to a difference string

snoc :: DString -> Char -> DString

O(1), Append a Char to a difference string

append :: DString -> DString -> DString

O(1), Appending difference strings

concat :: [DString] -> DString

O(spine), Concatenate difference strings

list :: b -> (Char -> DString -> b) -> DString -> b

O(length ds), difference list elimination, head, tail.

head :: DString -> Char

Return the head of the difference string

tail :: DString -> DString

Return the tail of the difference string

unfoldr :: (b -> Maybe (Char, b)) -> b -> DString

Unfoldr for difference strings

foldr :: (Char -> b -> b) -> b -> DString -> b

Foldr over difference strings