Tryinig to program arduino in pure c, get the following error: expected '=', ',', ';', 'asm' or '__attribute__' before 'Print'|

Question

我在 Arduino IDE 中写了一个程序（它涉及一些矩阵数学）。但是，我想尝试一些编译器选项。似乎没有一种简单的方法可以做到这一点，所以我转而尝试使用 CodeBlocks 编写一个纯 c 程序。我得到了眨眼的例子，但我想利用串行库。我只是找到了 h 和 cpp 文件并将它们复制到包含我的 main.c 文件的文件夹中。 （我不知道这是否是正确的方法）。

现在我收到以下错误消息： Print.h|37|错误：在 'Print'|[ 之前需要“=”、“、”、“;”、'asm' 或“属性” =11=]

它抱怨的代码是我复制的标准代码之一类。

/*
  Print.h - Base class that provides print() and println()
  Copyright (c) 2008 David A. Mellis.  All right reserved.

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.

  This library is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/

#ifndef Print_h
#define Print_h

#include <inttypes.h>
#include <stdio.h> // for size_t

#include "WString.h"


#define DEC 10
#define HEX 16
#define OCT 8
#ifdef BIN // Prevent warnings if BIN is previously defined in "iotnx4.h" or similar
#undef BIN
#endif
#define BIN 2

class Print
{
  private:
    int write_error;
    size_t printNumber(unsigned long, uint8_t);
    size_t printFloat(double, uint8_t);
  protected:
    void setWriteError(int err = 1) { write_error = err; }
  public:
    Print() : write_error(0) {}

    int getWriteError() { return write_error; }
    void clearWriteError() { setWriteError(0); }

    virtual size_t write(uint8_t) = 0;
    size_t write(const char *str) {
      if (str == NULL) return 0;
      return write((const uint8_t *)str, strlen(str));
    }
    virtual size_t write(const uint8_t *buffer, size_t size);
    size_t write(const char *buffer, size_t size) {
      return write((const uint8_t *)buffer, size);
    }

    // default to zero, meaning "a single write may block"
    // should be overriden by subclasses with buffering
    virtual int availableForWrite() { return 0; }

    size_t print(const __FlashStringHelper *);
    size_t print(const String &);
    size_t print(const char[]);
    size_t print(char);
    size_t print(unsigned char, int = DEC);
    size_t print(int, int = DEC);
    size_t print(unsigned int, int = DEC);
    size_t print(long, int = DEC);
    size_t print(unsigned long, int = DEC);
    size_t print(double, int = 2);
    size_t print(const Printable&);

    size_t println(const __FlashStringHelper *);
    size_t println(const String &s);
    size_t println(const char[]);
    size_t println(char);
    size_t println(unsigned char, int = DEC);
    size_t println(int, int = DEC);
    size_t println(unsigned int, int = DEC);
    size_t println(long, int = DEC);
    size_t println(unsigned long, int = DEC);
    size_t println(double, int = 2);
    size_t println(const Printable&);
    size_t println(void);

    virtual void flush() { /* Empty implementation for backward compatibility */ }
};

#endif

我怀疑问题的出现是因为编译器将代码视为 c-code，而它是 c++ 代码。我使用 GNU AVR GCC 编译器，它应该能够执行 c 和 c++ 代码。我是否需要向我的 header 添加一些内容以表明它涉及 C++ 代码？

Answer 1

类 是一个 C++ 特性，在 C 中不存在，所以 C 编译器正确地给你一个关于它们的错误，因为你正在尝试使用 "pure C"。虽然报错有点迷糊，意思是class不是C中的关键字，所以认为是标识符，连续看到两个标识符就糊涂了