Portability | portable |
---|---|

Stability | experimental |

Maintainer | Bryan O'Sullivan <bos@mailrank.com> |

Storage and retrieval of data with automatic conflict resolution.

- class Show a => Resolvable a where
- resolve :: a -> a -> a

- newtype ResolvableMonoid a = RM {
- unRM :: a

- data ResolutionFailure = RetriesExceeded

# Documentation

class Show a => Resolvable a whereSource

A type that can automatically resolve a vector clock conflict between two or more versions of a value.

Instances must be symmetric in their behaviour, such that the following law is obeyed:

resolve a b == resolve b a

Otherwise, there are no restrictions on the behaviour of `resolve`

.
The result may be `a`

, `b`

, a value derived from `a`

and `b`

, or
something else.

If several conflicting siblings are found, `resolve`

will be
applied over all of them using a fold, to yield a single
"winner".

Resolvable a => Resolvable (Maybe a) | |

(Eq a, Show a, Monoid a) => Resolvable (ResolvableMonoid a) |

newtype ResolvableMonoid a Source

A newtype wrapper that uses the `mappend`

method of a type's
`Monoid`

instance to perform vector clock conflict resolution.

Typeable1 ResolvableMonoid | |

Eq a => Eq (ResolvableMonoid a) | |

Data a => Data (ResolvableMonoid a) | |

Ord a => Ord (ResolvableMonoid a) | |

Read a => Read (ResolvableMonoid a) | |

Show a => Show (ResolvableMonoid a) | |

ToJSON a => ToJSON (ResolvableMonoid a) | |

FromJSON a => FromJSON (ResolvableMonoid a) | |

Monoid a => Monoid (ResolvableMonoid a) | |

(Eq a, Show a, Monoid a) => Resolvable (ResolvableMonoid a) | |

IsContent a => IsContent (ResolvableMonoid a) |

data ResolutionFailure Source

Automated conflict resolution failed.

RetriesExceeded | Too many attempts were made to resolve a conflict, with each attempt resulting in another conflict. The number of retries that the library will attempt is high
(64). This makes it extremely unlikely that this exception will
be thrown during normal application operation. Instead, this
exception is most likely to be thrown as a result of a bug in
your application code, for example if your |