/**
 * MEL Lexer
 * Tokenizes MEL source code based on SPEC v0.3.1 Section 3
 */
import type { Diagnostic } from "../diagnostics/types.js";
import { type Token } from "./tokens.js";
/**
 * Result of lexical analysis
 */
export interface LexResult {
    tokens: Token[];
    diagnostics: Diagnostic[];
}
/**
 * Lexer for MEL source code
 */
export declare class Lexer {
    private source;
    private sourcePath?;
    private tokens;
    private diagnostics;
    private start;
    private current;
    private line;
    private column;
    constructor(source: string, sourcePath?: string);
    /**
     * Tokenize the source code
     */
    tokenize(): LexResult;
    private scanToken;
    private lineComment;
    private blockComment;
    private string;
    private number;
    private identifier;
    private systemIdentifier;
    private isAtEnd;
    private advance;
    private peek;
    private peekNext;
    private match;
    private newline;
    private isDigit;
    private isHexDigit;
    private isAlpha;
    private isAlphaNumeric;
    private currentLocation;
    private positionAt;
    private addToken;
    private error;
    private getSourceLine;
}
/**
 * Tokenize MEL source code
 */
export declare function tokenize(source: string, sourcePath?: string): LexResult;