Interface IScyllaMap<TKey, TValue>

Common contract for key/value map collections (dictionary-like associative containers). Provides a minimal, allocation-free "try"-based surface for insertion, retrieval, and removal so that different map implementations - such as the managed open-addressing ScyllaMap<TKey, TValue> and the DOTS-native ScyllaMapDOTS<TKey, TValue> - can be used interchangeably through this interface.

Inherited Members
Namespace: Scylla.Core.Structures
Assembly: ScyllaCore.dll
Syntax
public interface IScyllaMap<TKey, TValue> : IScyllaCollection
Type Parameters
Name Description
TKey

The type of keys stored in the map. Reference-type keys must not be null when passed to any map operation; value-type keys have no restrictions.
TValue

The type of values associated with each key. null is a valid value for reference types; use ContainsKey(TKey) or TryGetValue(TKey, out TValue) to distinguish a stored null value from a missing key.
Remarks

All mutating operations use a "try"-pattern that returns a bool indicating success or failure rather than throwing for expected cases such as duplicate-key or capacity-full conditions. Only truly exceptional states (e.g. a null key) cause exceptions.

Thread safety is not guaranteed by this interface. Consult the ThreadSafety property of the concrete implementation, or use an explicit synchronized wrapper such as ScyllaMap<TKey, TValue>.SynchronizedScyllaMap.

Typical use cases include type-keyed registries, rule tables, dependency graphs, spatial indices, and any scenario that requires fast O(1) average-case key lookup without the overhead of Dictionary<TKey, TValue> allocation patterns.

Methods

ContainsKey(TKey)

Determines whether the map contains the specified key.

Declaration
bool ContainsKey(TKey key)
Parameters
Type Name Description
TKey key

The key to locate. Must not be null for reference-type keys; passing null may throw ArgumentNullException depending on the implementation.
Returns
Type Description
bool

true if an entry with the given key currently exists in the map; false if the key is not present.

TryAdd(TKey, TValue)

Attempts to insert a new key/value pair into the map. This operation does not overwrite an existing entry; use a separate set/update operation if upsert behaviour is required.

Declaration
bool TryAdd(TKey key, TValue value)
Parameters
Type Name Description
TKey key

The key to insert. Must not be null for reference-type keys. If a duplicate key is passed, the method returns false without modifying the map.
TValue value

The value to associate with key. null is permitted for reference types.
Returns
Type Description
bool

true if the pair was successfully added. false if the key already exists, if the map is at its fixed capacity and cannot grow, or if any other implementation-specific constraint prevents the insertion.

TryGetValue(TKey, out TValue)

Attempts to retrieve the value associated with the specified key.

Declaration
bool TryGetValue(TKey key, out TValue value)
Parameters
Type Name Description
TKey key

The key to look up. Must not be null for reference-type keys.
TValue value

When this method returns true, contains the value associated with key. When this method returns false, contains the default value for TValue. Note that a stored value of null (for reference types) is indistinguishable from "not found" via the output parameter alone; use the return value to distinguish the two cases.
Returns
Type Description
bool

true if the key exists and value has been set; false if the key was not found.

TryRemove(TKey)

Attempts to remove the entry associated with the specified key. For open-addressing implementations such as ScyllaMap<TKey, TValue>, removal places a tombstone in the slot to preserve probe-chain integrity; the slot is reclaimed during a subsequent rehash or compaction.

Declaration
bool TryRemove(TKey key)
Parameters
Type Name Description
TKey key

The key to remove. Must not be null for reference-type keys.
Returns
Type Description
bool

true if the key was found and the entry was removed; false if the key does not exist in the map.

Extension Methods