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#pragma once
#include "Api.h"
/**
* @file VM.h
* @brief Declares the logic execution boundary for relational and higher-order workloads.
*/
namespace nt
{
/**
* @class VM
* @brief Hosts the first-order logic (FOL) and second-order logic (SOL) cores.
*
* This partitioning exists to ensure retrieval terminates when execution is
* constrained to first-order logic.
*
* - Tarski runtime (FOL): a relational engine that implements Tarski's
* relational calculus. It uses a deterministic Volcano-iterator model to
* perform relational algebra operations such as joins, projections, and
* selects directly against the CursorManager and a prepared plan.
*
* - Karuta runtime (SOL): an isolated WAM-based environment for
* higher-order logic programming. It handles recursion, choice points, and
* other programming constructs that do not guarantee termination.
*
* @remark Lazy evaluation and paging strategy
*
* Both the Tarski first-order engine and the Karuta second-order engine are
* strictly pull-based. Data is streamed lazily from the CursorManager to
* preserve a constant memory footprint regardless of relation size.
*
* Pipeline dynamics:
* - Demand-driven: the Karuta WAM requests a fact only when a goal needs
* satisfaction. A request propagates down the algebra tree as a chain of
* Next() calls.
*
* - Short-circuiting: if the Karuta engine finds a solution or reaches a
* failure that invalidates a branch, the Tarski iterator is discarded or
* reset without materializing the remaining tuples.
*
* - Resource stewardship: by maintaining laziness up to the highest logical
* level, the runtime minimizes pressure on ObjectManager and keeps
* snapshots pinned through LifecycleManager::Monitor only for the minimum
* time required.
*/
class NT_API VM
{
};
}
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