C++闭包探索

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#include<iostream>
using namespace std;
/*
 * 利用c++类嵌套内部类实现闭包
 */
class ITest
{
	public:
		void operator() ()
		{
			process();
		}

		virtual ~ITest(){}
	protected:
		virtual void process() = 0;
};
ITest * test()
{
	static int count = 0;
	class Test: public ITest
	{
		public:
			virtual void process()
			{
				cout << "嵌套内部类:" << " Count is " << count++ <<endl;
			}
	};

	return new Test();
}
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/*
 *  利用函数内部类实现闭包
 */
typedef void (*Func)(const char *);

Func testFunc()
{
	static int count = 100;

	class Test
	{
		public:
			static void process(const char * pName = NULL)
			{
				if(pName == NULL){
					pName = "moses";
				}
				cout << "函数内部类:"<< pName << " Count is "<< count-- << endl;
			}
	};

	return Test::process;
}
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/*
 * c++新特性lambda表达式实现闭包
 */
std::function<void(const char *)> lambdaTest()
{
	int count = 100;

	auto func = [count] (const char * pName = NULL) mutable {
		if(pName == NULL){
			pName = "moses";
		}
		cout << "lambda : " << pName << " Count is " << count-- << endl;
	};

	return func;
}