Graphula.Internal

Documentation

class MonadGraphulaBackend m where

Associated Types

type Logging m :: Type -> Constraint

A constraint provided to log details of the graph to some form of persistence. This is used by runGraphulaLogged to store graph nodes as Shown Text values

Methods

askGen :: m (IORef QCGen)

logNode :: Logging m a => a -> m ()

Instances

(MonadGraphulaBackend m, MonadIO m) => MonadGraphulaBackend (GraphulaLoggedT m)

Defined in Graphula

Associated Types

type Logging (GraphulaLoggedT m) :: Type -> Constraint

Methods

askGen :: GraphulaLoggedT m (IORef QCGen)

logNode :: Logging (GraphulaLoggedT m) a => a -> GraphulaLoggedT m ()

MonadIO m => MonadGraphulaBackend (GraphulaT n m)

Defined in Graphula

Associated Types

type Logging (GraphulaT n m) :: Type -> Constraint

Methods

askGen :: GraphulaT n m (IORef QCGen)

logNode :: Logging (GraphulaT n m) a => a -> GraphulaT n m ()

class GHasDependencies nodeTyProxy depsTyProxy node deps where

Methods

genericDependsOn :: nodeTyProxy -> depsTyProxy -> node -> deps -> node

Instances

(TypeError ('Text "Use \8216()\8217 instead of \8216Void\8217 for datatypes with no dependencies in" :$$: DependenciesTypeInstance nodeTy depsTy) :: Constraint) => GHasDependencies (Proxy nodeTy) (Proxy depsTy) node Void

Defined in Graphula.Internal

Methods

genericDependsOn :: Proxy nodeTy -> Proxy depsTy -> node -> Void -> node

(TypeError ('Text "A datatype with no constructors can't use the dependencies in" :$$: DependenciesTypeInstance nodeTy depsTy) :: Constraint) => GHasDependencies (Proxy nodeTy) (Proxy depsTy) Void (Either deps rest)

Defined in Graphula.Internal

Methods

genericDependsOn :: Proxy nodeTy -> Proxy depsTy -> Void -> Either deps rest -> Void

GHasDependencies (Proxy nodeTy) (Proxy depsTy) Void (Either () Void)

Defined in Graphula.Internal

Methods

genericDependsOn :: Proxy nodeTy -> Proxy depsTy -> Void -> Either () Void -> Void

(TypeError ('Text "Cannot automatically find dependencies for sum type or use a sum type as a dependency in" :$$: DependenciesTypeInstance nodeTy depsTy) :: Constraint) => GHasDependencies (Proxy nodeTy) (Proxy depsTy) (Either left1 (Either right1 rest1)) (Either left2 (Either right2 rest2))

Defined in Graphula.Internal

Methods

genericDependsOn :: Proxy nodeTy -> Proxy depsTy -> Either left1 (Either right1 rest1) -> Either left2 (Either right2 rest2) -> Either left1 (Either right1 rest1)

(TypeError ('Text "Cannot automatically use a sum type as dependencies in" :$$: DependenciesTypeInstance nodeTy depsTy) :: Constraint) => GHasDependencies (Proxy nodeTy) (Proxy depsTy) (Either node Void) (Either left (Either right rest))

Defined in Graphula.Internal

Methods

genericDependsOn :: Proxy nodeTy -> Proxy depsTy -> Either node Void -> Either left (Either right rest) -> Either node Void

(TypeError ('Text "Cannot automatically find dependencies for sum type in" :$$: DependenciesTypeInstance nodeTy depsTy) :: Constraint) => GHasDependencies (Proxy nodeTy) (Proxy depsTy) (Either left (Either right rest)) (Either deps Void)

Defined in Graphula.Internal

Methods

genericDependsOn :: Proxy nodeTy -> Proxy depsTy -> Either left (Either right rest) -> Either deps Void -> Either left (Either right rest)

(FindMatches nodeTy depsTy node deps ~ fields, GHasDependenciesRecursive (Proxy fields) node deps) => GHasDependencies (Proxy nodeTy) (Proxy depsTy) (Either node Void) (Either deps Void)

Defined in Graphula.Internal

Methods

genericDependsOn :: Proxy nodeTy -> Proxy depsTy -> Either node Void -> Either deps Void -> Either node Void

data KeySourceType

Constructors

SourceDefault

Generate keys using the database's DEFAULT strategy

SourceArbitrary

Generate keys using the Arbitrary instance for the Key

SourceExternal

Always explicitly pass an external key

class GenerateKeyInternal (s :: KeySourceType) a where

Handle key generation for SourceDefault and SourceArbitrary

Ths could be a single-parameter class, but carrying the a around lets us give a better error message when node is called instead of nodeKeyed.

Associated Types

type KeyConstraint s a :: Constraint

Methods

generateKey :: KeyConstraint s a => Gen (Maybe (Key a))

Instances

GenerateKeyInternal 'SourceDefault a

Defined in Graphula.Internal

Associated Types

type KeyConstraint 'SourceDefault a

Methods

generateKey :: Gen (Maybe (Key a))

GenerateKeyInternal 'SourceArbitrary a

Defined in Graphula.Internal

Associated Types

type KeyConstraint 'SourceArbitrary a

Methods

generateKey :: Gen (Maybe (Key a))

(TypeError ((((((((((('Text "Cannot generate a value of type " :<>: Quote ('ShowType a)) :<>: 'Text " using ") :<>: Quote ('Text "node")) :<>: 'Text " since") :$$: 'Text "") :$$: (('Text " instance HasDependencies " :<>: 'ShowType a) :<>: 'Text " where")) :$$: (((('Text " " :<>: 'Text "type KeySource ") :<>: 'ShowType a) :<>: 'Text " = ") :<>: 'ShowType 'SourceExternal)) :$$: 'Text "") :$$: 'Text "Possible fixes include:") :$$: ((('Text "\8226 Use " :<>: Quote ('Text "nodeKeyed")) :<>: 'Text " instead of ") :<>: Quote ('Text "node"))) :$$: ((((('Text "\8226 Change " :<>: Quote ('Text "KeySource " :<>: 'ShowType a)) :<>: 'Text " to ") :<>: 'Text "'SourceDefault") :<>: 'Text " or ") :<>: 'Text "'SourceArbitrary")) :: Constraint) => GenerateKeyInternal 'SourceExternal a

Explicit instance for SourceExternal to give an actionable error message

Rendered:

Cannot generate a value of type ‘X’ using ‘node’ since

  instance HasDependencies X where
    type KeySource X = 'SourceExternal

Possible fixes include:
• Use ‘nodeKeyed’ instead of ‘node’
• Change ‘KeySource X’ to 'SourceDefault or 'SourceArbitrary

Defined in Graphula.Internal

Associated Types

type KeyConstraint 'SourceExternal a

Methods

generateKey :: Gen (Maybe (Key a))

class NoConstraint a

Graphula accepts constraints for various uses. Frontends do not always utilize these constraints. NoConstraint is a universal class that all types inhabit. It has no behavior and no additional constraints.

Instances

NoConstraint a

Defined in Graphula.Internal