data

tuprolog.solve.data

Custom data: values that libraries and programs attach to the state of a solver.

Primitives and Prolog programs can store arbitrary values, by key, in the state of a solver (its tuprolog.solve.ExecutionContext), in three tiers, by how long values survive:

• persistent data lives as long as the solver, i.e. across queries;
• durable data lives during a query, longer than ephemeral data;
• ephemeral data is the first to be discarded, e.g. at each resolution step.

Prolog programs read and write them with get_persistent/2 and set_persistent/2 (and the durable and ephemeral variants); primitives with the side effects of tuprolog.solve.sideffects (e.g. set_persistent_data).

Main types and functions:

• CustomData: a JVM map from keys (strings) to values, created by custom_data;
• CustomDataStore: the three tiers of a solver, created by custom_data_store;
• EMPTY_DATA and EMPTY_DATA_STORE.

Examples:

>>> from tuprolog.solve.prolog import prolog_solver
>>> solver = prolog_solver()
>>> solver.solve_once("set_persistent(counter, 1)").is_yes
True
>>> solver.solve_once("get_persistent(counter, Value)")["Value"]
1

CustomDataStore module-attribute

CustomDataStore = _data.CustomDataStore

The custom data of a solver, in three tiers: persistent, durable and ephemeral.

Each tier is a CustomData map. Members: persistent, durable, ephemeral, copy(persistent, durable, ephemeral), discard_ephemeral() (a copy without ephemeral data), preserve_persistent() (a copy with persistent data only). Create stores with custom_data_store.

CustomData module-attribute

CustomData = Map

Custom data: a JVM map from keys (strings) to arbitrary values, created by custom_data.

EMPTY_DATA module-attribute

EMPTY_DATA: CustomData = _jutils.Collections.emptyMap()

The empty custom data.

EMPTY_DATA_STORE module-attribute

EMPTY_DATA_STORE: CustomDataStore = CustomDataStore.empty()

The custom data store with no data in any tier.

custom_data

custom_data(
    data: Mapping[str, Any] = {}, **kwargs: Any
) -> CustomData

Creates custom data, i.e. a JVM map from keys to values.

Parameters:

Name	Type	Description	Default
data	Mapping[str, Any]	The values, by key.	{}
**kwargs	Any	More values, by key.	{}

Returns:

Type	Description
CustomData	The custom data.

Examples:

>>> custom_data({"a": 1}, b="x")
{a=1, b=x}

custom_data_store

custom_data_store(
    persistent: CustomData = EMPTY_DATA,
    durable: CustomData = EMPTY_DATA,
    ephemeral: CustomData = EMPTY_DATA,
) -> CustomDataStore

Creates a custom data store, from the data of its three tiers.

Parameters:

Name	Type	Description	Default
persistent	CustomData	The data living as long as the solver.	EMPTY_DATA
durable	CustomData	The data living during a query.	EMPTY_DATA
ephemeral	CustomData	The data discarded first.	EMPTY_DATA

Returns:

Type	Description
CustomDataStore	The custom data store.

Examples:

>>> custom_data_store(persistent=custom_data(a=1))
CustomDataStore(persistent={a=1}, durable={}, ephemeral={})