/**
 * Lexer for tokenizing formula strings
 */
/**
 * Token types for formula lexing
 */
export type TokenType = 'NUMBER' | 'STRING' | 'BOOLEAN' | 'IDENTIFIER' | 'FUNCTION' | 'OPERATOR' | 'LPAREN' | 'RPAREN' | 'LBRACE' | 'RBRACE' | 'LBRACKET' | 'RBRACKET' | 'COMMA' | 'SEMICOLON' | 'COLON' | 'DOLLAR' | 'EXCLAMATION' | 'AT' | 'HASH' | 'INFINITY' | 'ERROR' | 'EOF' | 'WHITESPACE';
/**
 * Token interface
 */
export interface Token {
    type: TokenType;
    value: string;
    position: {
        start: number;
        end: number;
    };
}
/**
 * Lexer class for tokenizing formula strings
 */
export declare class Lexer {
    private input;
    private position;
    private tokens;
    constructor(input: string);
    /**
     * Tokenize the entire input string
     */
    tokenize(): Token[];
    /**
     * Get the next token from the input
     */
    private nextToken;
    /**
     * Read a whitespace token
     */
    private readWhitespace;
    /**
     * Read a number token
     */
    private readNumber;
    /**
     * Read a string token (enclosed in double quotes)
     */
    private readString;
    /**
     * Read a sheet name (enclosed in single quotes)
     */
    private readSheetName;
    /**
     * Read an error token (e.g., #DIV/0!)
     */
    private readError;
    /**
     * Read an identifier (cell reference, function name, boolean)
     */
    private readIdentifier;
    /**
     * Check if current position is whitespace
     */
    private isWhitespace;
    /**
     * Check if a character is whitespace
     */
    private isWhitespaceChar;
    /**
     * Check if a character is a digit
     */
    private isDigit;
    /**
     * Check if a character is alphabetic
     */
    private isAlpha;
    /**
     * Check if a character is alphanumeric
     */
    private isAlnum;
    /**
     * Check if a character can be part of an identifier
     * This includes letters, certain symbols that are commonly used in column names
     */
    private isIdentifierChar;
    /**
     * Peek ahead to check if we have a table selector
     */
    private peekSelector;
}
/**
 * Quick tokenization function
 */
export declare function tokenize(input: string): Token[];
/**
 * Token stream for parser consumption
 */
export declare class TokenStream {
    private tokens;
    private position;
    constructor(tokens: Token[]);
    /**
     * Peek at current token without consuming
     */
    peek(): Token;
    /**
     * Peek ahead by n tokens
     */
    peekAhead(n: number): Token | null;
    /**
     * Peek at the next token without consuming
     */
    peekNext(): Token | null;
    /**
     * Consume current token and advance
     */
    consume(): Token;
    /**
     * Check if current token matches type
     */
    match(type: TokenType): boolean;
    /**
     * Check if current token matches value
     */
    matchValue(value: string): boolean;
    /**
     * Consume token if it matches type
     */
    consumeIf(type: TokenType): Token | null;
    /**
     * Check if at end of stream
     */
    isAtEnd(): boolean;
    /**
     * Get current position in stream
     */
    getPosition(): number;
    /**
     * Set position in stream
     */
    setPosition(position: number): void;
    /**
     * Get all tokens
     */
    getTokens(): Token[];
}