Namespace Libplanet.Action

Classes

ActionEvaluation<T>

A record type to represent an evaluation plan and result of a single action (T).

ActionTypeAttribute

Indicates that an action class (i.e., a class implementing IAction) can be held by transactions and blocks. It also gives an action class a TypeIdentifier for serialization and deserialization.

AddressStateMap

An immutable key–value data structure to represent states of multiple accounts. Keys are an account Address, and values are their state.

Since this implements IImmutableDictionary<TKey,TValue> interface, the usage is same.

MissingActionTypeException

The exception that is thrown when an action class without ActionTypeAttribute is tried to used with PolymorphicAction<T>.

PolymorphicAction<T>

A decorator to enable subtype polymorphism for action classes.

By convention, concrete action subclasses are named with verb phrases, e.g., Heal, Sell.

One downside of this compared to the vanilla IAction is the fact that it uses reflection under the hood. This may cause compatibility issues on certain platforms, and is slightly slower.

Interfaces

IAccountStateDelta

An interface to manipulate account states with maintaining the set of UpdatedAddresses.

It is like a map which is virtually initialized such that every possible Address exists and is mapped to null. That means that:

• it does not have length,
• its index getter never throws KeyNotFoundException, but returns null instead, and
• filling an Address with null state cannot be distinguished from the Address having never been set to any state.

IAction

An in-game action. Every action should be replayable, because multiple nodes in a network should execute an action and get the same result.

A “class” which implements this interface is analogous to a function, and its instance is analogous to a partial function application, in other words, a function with some bound arguments. Those parameters that will be bound at runtime should be represented as fields or properties in an action class, and bound argument values to these parameters should be received through a constructor parameters of that class.

IActionContext

Contextual data determined by a transaction and a block. Passed to Execute(IActionContext) method.

IRandom

An pseudorandom number generator interface equivalent to Random.

Although these two types have similar shapes, they are not compatible (i.e., disallowed to be casted to each other).

Delegates

AccountStateGetter

An delegate to provide read-only view of account states.

Gets an account state of the given address.

If the given address has never been set its account status, returns null instead of throwing any exception.