amath/app/main/lexer.h

/*
 * Copyright (c) 2015-2017 Carsten Sonne Larsen  <cs@innolan.dk>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#ifndef _LEXER_H
#define _LEXER_H

/**
 * @file  lexer.h
 * @brief Application logic tied to Lexer.
 *
 */

#include "main/token.h"

/**
 * @brief Encapsulates an lexical analyzer. Provides token for the parser.
 *
 * More info on lexical analysis is available at Wikipedia:
 * http://en.wikipedia.org/wiki/Lexical_analysis
 *
 */
class Lexer {
public:
    Lexer(const char *input);
    ~Lexer();

    void Tokenize();
    Token* GetFirstToken();
    char* GetInput();
    static char* FindKeyword(Symbol symbol);

private:
    char *input; // Input to process by lexer
    char *str;   // Pointer to char being processed
    unsigned int pos;
    Token* first;
    Token* current;

    void GetNextToken();
    bool GetOperator();
    bool GetQuotedIdent();
    bool GetLitteral();
    bool GetDigitValue();
    bool ShouldSkip(char character);
    Symbol FindKeyword(const char *ident);
};

#endif