Structure initialization error: could not convert from ‘<brace-enclosed initializer list>’ to structure

Question

我有以下代码：

struct Vec { double x=0, y=0, z=0; };

Vec orig = {1,2,3};

GCC 4.8.4 显示以下错误：

error: could not convert ‘{1, 2, 3}’ from ‘<brace-enclosed initializer list>’ to ‘Vec’
 Vec orig = {1,2,3};
                  ^

我改的时候去掉等号

Vec orig {1,2,3};

出现另一个错误：

error: no matching function for call to ‘Vec::Vec(<brace-enclosed initializer list>)’
 Vec orig {1,2,3};
                ^

如何在不创建构造函数的情况下正确初始化结构？

Answer 1

看起来您正在使用 c++11，但还不是 c++14。

一旦你提供了默认成员初始值设定项，class就不再是聚合，你就不能使用聚合初始化.

https://en.cppreference.com/w/cpp/language/aggregate_initialization

An aggregate is one of the following types:

...

class type (typically, struct or union), that has

...

no default member initializers (until c++14)

Structure initialization error: could not convert from ‘<brace-enclosed initializer list>’ to structure

Structure initialization error: could not convert from ‘<brace-enclosed initializer list>’ to structure

c++

structure

initializer-list

c++11