Package-level declarations

A visitor over Clauses, dispatching to a specific callback depending on the clause's concrete kind (onDirective/onFact/onRule/onClause for anything else), via listen.

The result of splitting a collection of Clauses (typically a whole Theory) into the pieces of state a it.unibo.tuprolog.solve.Solver must be seeded with when loading it: plain clauses bound for the static/dynamic knowledge bases, plus everything expressed via directives (:- Goal facts) -- declared operators, flags (flagStore), goals to run at load time (initialGoals), and other theories to load (includes).

The concrete ClausePartition/DirectiveSelector implementation, lazily partitioning source's clauses on first access to any of ClausePartition's properties (and caching the result thereafter). Plain Rules/Facts are routed to dynamicClauses or staticClauses depending on whether their signature was declared dynamic/1 or static/1 by a directive, falling back to staticByDefault when neither was declared.

A ClauseListener refinement that further dispatches Directives (:- Goal clauses) depending on which of patterns their body unifies with, rather than treating every directive alike via ClauseListener.onDirective.

The concrete DirectiveListener recognizing every directive pattern 2P-Kt gives special treatment to when loading a knowledge base: dynamic/1, static/1 (declaring a predicate's storage), initialization/1/solve/1 (a goal to run at load time), include/1/load/1 (another theory to load), op/3 (operator declaration), and set_flag/2/set_prolog_flag/2 (flag assignment). Each recognized pattern is routed to the corresponding on* callback (onDynamic, onStatic, onSolve, onLoad, onOperator, onSetFlag); anything else falls back to ClauseListener.onDirective.

Partitions this Theory's clauses into a ClausePartition, using its own Theory.unificator by default.

Partitions this collection of clauses into a ClausePartition, using unificator to match directive patterns.

Null-safe ClausePartition.plus: merges two possibly-null partitions, returning null only if both are.