/**
 * A text reader.
 *
 * It internally holds a text pointer `pos`. It seeks for forward direction only.
 */
export interface TextReader {
    /** Return true if `pos` has reached to the end of the text. */
    eof: () => boolean;
    /** Skip(forward) `pos` by number of `delta` characters. */
    skip: (delta: number) => void;
    /** Skip(forward) `pos` to `newPos`. */
    skipTo: (newPos: number) => void;
    /** Read the text partially from `pos` to `end`(`end` not included) */
    readBy: (end: number) => string;
}
export declare function createTextReader(text: string): TextReader;
/**
 * A text scanner.
 *
 * It internally holds a text pointer `pos`. It seeks for forward direction only.
 */
export interface TextScanner {
    /** Return true if `pos` has reached to the end of the text. */
    eof: () => boolean;
    /** Return `pos`. */
    pos: () => number;
    /** advance `pos` number of `delta` or one character(s). */
    advance: (delta?: number) => void;
    /** advance `pos` to `newPos`. */
    advanceTo: (newPos: number) => void;
    /** Read a character at `pos` in `text` */
    getChar: () => string;
}
export declare function createTextScanner(text: string): TextScanner;