为什么可以这么初始化？

[独酌逸醉]

// TestVS2008.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <iostream>
using namespace std;

template <class T,size_t N>
struct block {
	typedef T	 				value_type;
	typedef value_type* 		pointer;
	typedef const value_type* 	const_pointer;
	typedef value_type& 		reference;
	typedef const value_type& 	const_reference;
	
	typedef ptrdiff_t 			difference_type;
	typedef size_t 				size_type;
	typedef pointer 			iterator;
	typedef const_pointer 		const_iterator;
	
	iterator begin() { return data; }
	iterator end() const { return data + N; }
	
	reference operator[] (size_type n) { return data[n]; }
	const_reference operator[] (size_type n) const { return data[n]; }
	
	size_type size() const { return N; }
	T data[N];
};

int _tmain(int argc, _TCHAR* argv[])
{
	block<int,5> b = {1,2,3,4,5}; // b不是一个数组为什么可以这样初始化？
	for (int i = 0; i < b.size() ; ++ i) 
		cout << b[i] << ' ';
	return 0;
}

[独酌逸醉]

恩，结贴！

[hqm475]

这是数组的初始化的一种方式啊，你也可以用循环给每个b[T]赋值

[耍宝王]

对于没有定义构造函数并且其全体数据成员均为 public 的类，可以采用与初始化数组元素相同的方式初始化其成员——C++ Primer

[ri_aje]

C++03 8.5.1.[1,2]


1 An aggregate is an array or a class (clause 9) with no user-declared constructors (12.1), no private or protected non-static data members (clause 11), no base classes (clause 10), and no virtual functions (10.3).

2 When an aggregate is initialized the initializer can contain an initializer-clause consisting of a brace-enclosed, comma-separated list of initializer-clauses for the members of the aggregate, written in increasing subscript or member order. If the aggregate contains subaggregates, this rule applies recursively to the members of the subaggregate.

[Example:
      struct A {
                int x;
                struct B {
                           int i;
                           int j;
                } b;
      } a = { 1, { 2, 3 } };
initializes a.x with 1, a.b.i with 2, a.b.j with 3. ]

block<int,5> 是个 aggregate

[Csuxiaowu]

我擦 什么东西 定义来定义去的
没见过这种初始化
Python ？？

[Csuxiaowu]

[Quote=引用 2 楼 pgplay 的回复:]

对于没有定义构造函数并且其全体数据成员均为 public 的类，可以采用与初始化数组元素相同的方式初始化其成员——C++ Primer
[/Quote]
我翻书找了半天没找到啊 告诉我下哪页？多谢了

[Csuxiaowu]

找到了 396页

[lovestefanie]

囧，可以的吧

[pengzhixi]

好了，可以结贴了。