export declare function decodeVlqLine(line: string): number[][];
export type LineMapping = {
    /** Generated column → source index, sorted by column. */
    entries: Array<{
        column: number;
        sourceIndex: number;
    }>;
};
/**
 * Decodes a sourcemap `mappings` string into per-line column → source-index
 * tables. Only the fields attribution needs; name/line positions are dropped.
 */
export declare function decodeMappings(mappings: string): LineMapping[];
/** Returns the source index active at (line, column), or undefined. */
export declare function sourceIndexAt(lines: LineMapping[], line: number, column: number): number | undefined;