type StringNode = StringTextNode | StringSequenceNode | StringChoiceNode;
type StringTextNode = {
    type: 'text';
    text: string;
};
type StringSequenceNode = {
    type: 'sequence';
    nodes: StringNode[];
};
type StringChoiceNode = {
    type: 'choice';
    nodes: StringNode[];
};
export type { StringNode, StringTextNode, StringSequenceNode, StringChoiceNode, };
/**
 * Converts a StringNode tree into all possible string variants.
 * - TextNode → single string
 * - SequenceNode → cartesian product of all parts
 * - ChoiceNode → flattened branches (deduplicated)
 */
export declare function nodeToStrings(node: StringNode | null): string[];