Question

我不确定为什么会收到此错误。该函数应返回true或false。所有变量都已定义，我得到的错误是：

/tmp/ccTspEHr.o: In function `main':
rectangles.cpp:(.text+0x169): undefined reference to `rectangle_name(std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::vector<Rectangle, std::allocator<Rectangle> >)'
rectangles.cpp:(.text+0x310): undefined reference to `rectangle_name(std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::vector<Rectangle, std::allocator<Rectangle> >)'
rectangles.cpp:(.text+0x7b0): undefined reference to `rectangle_name(std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::vector<Rectangle, std::allocator<Rectangle> >)'
collect2: ld returned 1 exit status

功能原型：

bool rectangle_name(string prompt, string invalid, string used, string n, vector<Rectangle> rectangle);

功能定义：

bool rectangle_name(string prompt, string invalid, string used, string & n, vector<Rectangle> rectangle)
//This function reads in a prompt and reads in the name of the rectangle or stop\

{
  cout << prompt;
  getline (cin, n);
  // do other stuff and return true or false
}

导致这些错误的原因是什么？

Answer 1

你宣布了

bool rectangle_name(string prompt, string invalid, string used, string n, vector<Rectangle> rectangle);
                                                                 ^^^^^^^

并定义了

bool rectangle_name(string prompt, string invalid, string used, string & n, vector<Rectangle> rectangle)
                                                                 ^^^^^^^

看第四个参数？声明string n和定义string & n。他们不匹配。使这两个匹配，错误将消失。

Answer 2

很简单。你应该定义这个功能。您将该函数声明为

bool rectangle_name(string prompt, string invalid, string used, string n, vector<Rectangle> rectangle);

但定义了另一个功能

bool rectangle_name(string prompt, string invalid, string used, string & n, vector<Rectangle> rectangle)

注意名称为'n'的参数声明。

如何修复编译器错误未定义的引用

2 个答案: