import type { FilterFieldGroupNode, FilterFieldLeafNode, FilterFieldListNode, FilterFieldNode, FilterFieldStatementNode } from '../types/tree-nodes.js';
/**
 * Check whether the given node is a filter field group node.
 * @internal
 */
export declare function isFilterFieldGroupNode(node: unknown): node is FilterFieldGroupNode;
/**
 * Check whether the given node is a filter field statement node.
 * @internal
 */
export declare function isFilterFieldStatementNode(node: unknown): node is FilterFieldStatementNode;
/**
 * Check whether the given node is a filter field list node.
 * @public
 */
export declare function isFilterFieldListNode(node: unknown): node is FilterFieldListNode;
/**
 * Check if the given token is a node holding a value.
 * Not necessarily a leaf node. E.g. a List has a value,
 * but the value consists of other tokens.
 * @internal
 */
export declare function isFilterFieldValueNode(node: unknown): node is FilterFieldLeafNode;
/**
 * Check whether the given node is a filter field leaf node.
 * @public
 */
export declare function isFilterFieldLeafNode(node: unknown): node is FilterFieldLeafNode;
/**
 * Check if the given token is a filter value.
 * @internal
 */
export declare function isFilterValue(token: FilterFieldLeafNode | FilterFieldListNode): boolean;
/**
 * Returns whether the current operator is valid for a position operator (start-with / ends-with / contains).
 * Only equals, not equals, and ends-with/not-ends-with (will be converted to contains/not-contains) are valid values.
 * @internal
 */
export declare function isValidPositionOperator(node: FilterFieldStatementNode): boolean;
/**
 * Returns whether the current operator is a a LogicalOperator. Either it has the type LogicalOperator or it has the
 * type Error and 'OR' or 'AND' as value (if the LogicalOperator is in an invalid position or 'OR' is used in the basic syntax).
 * @internal
 */
export declare function isLogicalOperator(node: FilterFieldNode): boolean;