Data.Clock.IntervalTree

An interval tree clock implementation as per Interval Tree Clocks: A Logical Clock for Dynamic Systems. Paper by Almeida, Paulo & Baquero, Carlos & Fonte, Victor. This implementation by Arne Winter.

Types

data Stamp

Constructors

Stamp ITCId ITCEvent

Instances

Eq Stamp

Defined in Data.Clock.IntervalTree

Methods

(==) :: Stamp -> Stamp -> Bool

(/=) :: Stamp -> Stamp -> Bool

Show Stamp

Defined in Data.Clock.IntervalTree

Methods

showsPrec :: Int -> Stamp -> ShowS

show :: Stamp -> String

showList :: [Stamp] -> ShowS

Generic Stamp

Defined in Data.Clock.IntervalTree

Associated Types

type Rep Stamp :: Type -> Type

Methods

from :: Stamp -> Rep Stamp x

to :: Rep Stamp x -> Stamp

type Rep Stamp

Defined in Data.Clock.IntervalTree

type Rep Stamp = D1 ('MetaData "Stamp" "Data.Clock.IntervalTree" "interval-tree-clock-0.2.0.0-inplace" 'False) (C1 ('MetaCons "Stamp" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 ITCId) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 ITCEvent)))

data ITCId

Constructors

ITCIdBranch ITCId ITCId

ITCIdOff

ITCIdOn

Instances

Eq ITCId

Defined in Data.Clock.IntervalTree

Methods

(==) :: ITCId -> ITCId -> Bool

(/=) :: ITCId -> ITCId -> Bool

Show ITCId

Defined in Data.Clock.IntervalTree

Methods

showsPrec :: Int -> ITCId -> ShowS

show :: ITCId -> String

showList :: [ITCId] -> ShowS

Generic ITCId

Defined in Data.Clock.IntervalTree

Associated Types

type Rep ITCId :: Type -> Type

Methods

from :: ITCId -> Rep ITCId x

to :: Rep ITCId x -> ITCId

type Rep ITCId

Defined in Data.Clock.IntervalTree

type Rep ITCId = D1 ('MetaData "ITCId" "Data.Clock.IntervalTree" "interval-tree-clock-0.2.0.0-inplace" 'False) (C1 ('MetaCons "ITCIdBranch" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 ITCId) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 ITCId)) :+: (C1 ('MetaCons "ITCIdOff" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "ITCIdOn" 'PrefixI 'False) (U1 :: Type -> Type)))

data ITCEvent

Constructors

ITCEventBranch !Integer ITCEvent ITCEvent

ITCEventLeaf !Integer

Instances

Eq ITCEvent

Defined in Data.Clock.IntervalTree

Methods

(==) :: ITCEvent -> ITCEvent -> Bool

(/=) :: ITCEvent -> ITCEvent -> Bool

Show ITCEvent

Defined in Data.Clock.IntervalTree

Methods

showsPrec :: Int -> ITCEvent -> ShowS

show :: ITCEvent -> String

showList :: [ITCEvent] -> ShowS

Generic ITCEvent

Defined in Data.Clock.IntervalTree

Associated Types

type Rep ITCEvent :: Type -> Type

Methods

from :: ITCEvent -> Rep ITCEvent x

to :: Rep ITCEvent x -> ITCEvent

type Rep ITCEvent

Defined in Data.Clock.IntervalTree

type Rep ITCEvent = D1 ('MetaData "ITCEvent" "Data.Clock.IntervalTree" "interval-tree-clock-0.2.0.0-inplace" 'False) (C1 ('MetaCons "ITCEventBranch" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Integer) :*: (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 ITCEvent) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 ITCEvent))) :+: C1 ('MetaCons "ITCEventLeaf" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Integer)))

Seed

seed :: Stamp

The seed stamp. The first peer is to use this, then fork others.

Operations

fork :: Stamp -> (Stamp, Stamp)

use to register new peers. one stamp must be consecutively owned be the forking peer. the other stamp owned by host.

join :: Stamp -> Stamp -> Stamp

inverse of fork. s = uncurry join (fork s) Note that the internal call to sumId may be partial, if the ITC Stamp was constructed through direct constructor usage. Using only fork and join as the safe API to create stamps will not lead to this inconsistency.

peek :: Stamp -> Stamp

Anonymizes this stamp. Useful when sending messages or logging debug stamps.

event :: Stamp -> Stamp

when something happened on this peer. use the new stamp afterwards.

Comparison

happenedBefore :: Stamp -> Stamp -> Bool

the `happened before` relation for two stamps. (Note that I am unsure whether this is really the same relation as described by Lamport). Use this to examine causality of stamps.

data StampComparison

Constructors

Before

A happened before B.

After

A happened after B.

Concurrent

A happened concurrent to B in logical time.

Instances

Eq StampComparison

Defined in Data.Clock.IntervalTree

Methods

(==) :: StampComparison -> StampComparison -> Bool

(/=) :: StampComparison -> StampComparison -> Bool

Show StampComparison

Defined in Data.Clock.IntervalTree

Methods

showsPrec :: Int -> StampComparison -> ShowS

show :: StampComparison -> String

showList :: [StampComparison] -> ShowS

stampCompare :: Stamp -> Stamp -> StampComparison

Compare two stamps. Note that stamp is not an instance of Ord because a <= b and b <= a does not imply a = b: rather that a happened concurrent to b per logical time.