/**
 * A declarative, serializable predicate AST evaluated against a plain fact bag. Predicates carry no
 * closures, so they survive save/load and stay deterministic — the reusable condition seam that
 * event-conditioned rules, quests, perks, and reactive AI gate on instead of hand-rolled callbacks.
 */
/** A leaf value a predicate can compare against — JSON-safe so predicates serialize cleanly. */
export type PredicateValue = string | number | boolean | null;
/** Dot path into a fact bag, e.g. `"hit.crit"` or `"attacker.team"`. */
export type PredicatePath = string;
/**
 * One node of the predicate tree. Combinators (`all`/`any`/`not`) nest; leaf comparators read a
 * dot path from the facts and compare it. `has` passes when the path resolves to a non-nullish value.
 */
export type Predicate = {
    readonly all: readonly Predicate[];
} | {
    readonly any: readonly Predicate[];
} | {
    readonly not: Predicate;
} | {
    readonly eq: readonly [PredicatePath, PredicateValue];
} | {
    readonly ne: readonly [PredicatePath, PredicateValue];
} | {
    readonly gt: readonly [PredicatePath, number];
} | {
    readonly gte: readonly [PredicatePath, number];
} | {
    readonly lt: readonly [PredicatePath, number];
} | {
    readonly lte: readonly [PredicatePath, number];
} | {
    readonly in: readonly [PredicatePath, readonly PredicateValue[]];
} | {
    readonly has: PredicatePath;
};
/** Plain, serializable bag of facts a predicate reads by dot path. */
export type PredicateFacts = Record<string, unknown>;
/**
 * Read a dot path out of a fact bag, descending only through plain objects. Returns `undefined` when
 * any segment is missing or non-traversable. Bounded by the path's segment count.
 *
 * @capability declarative-predicate serializable data-driven conditions with no callbacks in saved content
 */
export declare function readPath(facts: PredicateFacts, path: PredicatePath): unknown;
/**
 * Evaluate a predicate against a fact bag. An omitted predicate matches unconditionally, so callers
 * can treat "no condition" and "always" identically. Pure and deterministic — no allocation beyond
 * path splits and no reliance on evaluation order between sibling clauses.
 *
 * @capability declarative-predicate serializable data-driven conditions with no callbacks in saved content
 */
export declare function evaluatePredicate(predicate: Predicate | undefined, facts: PredicateFacts): boolean;