API Reference > presentation-common > Core Core Common types used all across Presentation packages. Classes Name Description KeySet A class that holds multiple KeySet.Key objects. PresentationError An error type thrown by Presentation APIs. RegisteredRuleset A ruleset that is registered in a ruleset manager. RulesetsFactory A factory class that can be used to create presentation rulesets targeted towards Constants Name Description DEFAULT_KEYS_BATCH_SIZE Default (recommended) keyset batch size for cases when it needs to be sent Enumerations Name Description LoggingNamespaces Enum of logging namespaces used by Presentation library. Deprecated PresentationStatus Status codes used by Presentation APIs. RequestPriority Enumeration of standard request priorities. VariableValueTypes Possible variable value types Global Functions Name Description getInstancesCount Get total number of instances included in the supplied key set. Interfaces Name Description ClassInfoJSON A serialized version of ClassInfoJSON.ClassInfo ContentDescriptorRequestOptions Request type for content descriptor requests ContentRequestOptions Request type for content requests Deprecated DisplayLabelRequestOptions Request type for label requests DisplayLabelsRequestOptions Request type for labels requests DistinctValuesRequestOptions Request type for distinct values' requests EnumerationChoice A single choice in enumeration EnumerationInfo Enumeration information ExtendedContentRequestOptions Request type for content requests ExtendedHierarchyRequestOptions Request type for hierarchy requests HierarchyCompareInfoJSON JSON representation of HierarchyCompareInfoJSON.HierarchyCompareInfo. HierarchyCompareOptions Data structure for comparing a hierarchy after ruleset or ruleset variable changes. HierarchyRequestOptions Base request type for hierarchy requests Deprecated InstanceKeyJSON A serialized version of InstanceKeyJSON.InstanceKey KeySetJSON A data structure of serialized KeySet KindOfQuantityInfo Kind of quantity information LabelRequestOptions Request type for label requests Deprecated NodeDeletionInfo Information about node deletion. NodeDeletionInfoJSON JSON representation of NodeDeletionInfo. NodeInsertionInfo Information about node insertion. NodeInsertionInfoJSON JSON representation of NodeInsertionInfo. NodeUpdateInfo Information about node update. NodeUpdateInfoJSON JSON representation of NodeUpdateInfo. PagedResponse A structure for paged responses PageOptions Paging options PropertyInfoJSON A serialized version of PropertyInfoJSON.PropertyInfo RelatedClassInfoJSON A serialized version of RelatedClassInfoJSON.RelatedClassInfo RequestOptions A generic request options type used for both hierarchy and content requests RequestOptionsWithRuleset Options for requests that require presentation ruleset. RulesetVariable Data structure for representing ruleset variable. RulesetVariableJSON JSON representation of RulesetVariable. SelectionScopeRequestOptions Request options used for selection scope related requests StrippedRelatedClassInfo Data structure that contains a subset of StrippedRelatedClassInfo.RelatedClassInfo required to ValuesDictionary A dictionary data structure. Namespaces Name Description ClassInfo HierarchyCompareInfo InstanceKey Key PartialHierarchyModification PropertyInfo RelatedClassInfo RelationshipPath Type Aliases Name Description ClassId Type of an ECClass ID. ComputeDisplayValueCallback Definition of a function for calculating a display value. InstanceId Type of an ECInstance ID. Keys A type for multiple keys that identify something in iModel.js application Omit Create a type with T properties excluding properties listed in K. Paged A wrapper type that injects PageOptions into supplied type PartialHierarchyModificationJSON JSON representation of PartialHierarchyModificationJSON.PartialHierarchyModification. PresentationDataCompareOptions Data structure for comparing presentation data after ruleset or ruleset variable changes. Deprecated PrimitivePropertyValue Value of a primitive property. RelationshipPathJSON Serialized RelationshipPathJSON.RelationshipPath StrippedRelationshipPath Data structure that contains a subset of StrippedRelationshipPath.RelationshipPath required to Subtract Create a type with T properties excluding all properties in type K. VariableValue Union of all supported variable value types VariableValueJSON JSON representation of VariableValue Last Updated: 15 June, 2021