Data.Algorithm.Diff3

An implementation of a 3-way merge algorithm.

Documentation

data Hunk a

A hunk is a collection of changes that occur in a document. A hunk can be some changes only in A, only in B, in both A & B (equally), or conflicting between A, B and the original document. All hunks take 3 constructors, which are, in order - the elements in the left document, the original document, and the right document. This order matches the order of parameters to diff3.

Constructors

LeftChange [a]

RightChange [a]

Unchanged [a]

Conflict [a] [a] [a]

Instances

Functor Hunk

Eq a => Eq (Hunk a)

Show a => Show (Hunk a)

diff3 :: Eq a => [a] -> [a] -> [a] -> [Hunk a]

Perform a 3-way diff against 2 documents and the original document. This returns a list of triples, where each triple contains all parts of the original document that either agree on 2 or 3 sides, or conflict. This can be considered a 'low level' interface to the 3-way diff algorithm - you may be more interested in merge and toHunks, which provide a higher level interface.

merge :: [Hunk a] -> Either [Hunk a] [a]