一个简单的DSL实例

// NewProcess.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include <iostream>
#include <stdarg.h>

using namespace std;

typedef unsigned int(*_do_sth)();
typedef void(*_fail_call)(unsigned int);
typedef void(*_success_call)(unsigned int);

unsigned int gResult = 0;

void _process_start();
void _transation_start();
void _fail_rollback(_success_call a, _fail_call b, unsigned int result);
void _fail_rollback_call(unsigned int result);
void _success_submit_call(unsigned int result);
void _transation_end(void(*_fail_rollback)(_success_call, _fail_call, unsigned int), _success_call a, _fail_call b, unsigned int result);
void _sequence(_do_sth a, ...);

unsigned int _do_A();
unsigned int _do_B();

#define _RESULTBITMAP gResult
#define __process_start _process_start();
#define __fail_rollback    _fail_rollback
#define __transation_start _transation_start();
#define __transation_end(submitcall,rollbackcall)   _transation_end(__fail_rollback,##submitcall,##rollbackcall,_RESULTBITMAP);
#define __sequence         _sequence
#define __sequence_end     ;
#define __process_end     ;

/* DSL */

int _tmain(int argc, _TCHAR* argv[])
{
	__process_start
	{
		__transation_start
		{
			__sequence
			(
				_do_A,
				_do_B

			)
			__sequence_end
		}
		__transation_end(_success_submit_call, _fail_rollback_call)		
		
	}
	__process_end

	return 0;
}

/* 
业务函数
*/

unsigned int _do_A()
{
	cout << "Do A." << endl;
	return 0; /* ok */
	//return 1; /* fail */
}
unsigned int _do_B()
{
	cout << "Do B." << endl;
	return 0; /* ok */
	//return 1; /* fail */
}

/* 执行框架相关函数 */

void _process_start()
{
	cout << "Process start." << endl;
}

void _transation_start()
{
	cout << "Transation start!" << endl;
}
void _transation_end(void(*_fail_rollback)(_success_call,_fail_call, unsigned int), _success_call a, _fail_call b, unsigned int result)
{
	_fail_rollback(a, b, result);
	cout << "Transation end!" << endl;
}

void _fail_rollback(_success_call a, _fail_call b, unsigned int result)
{
	/* 0-ok !0-fail */
	if ((result>>31))
	{
		cout << "Transation fail rollback..." << endl;
		b(result);
	}
	else
	{
		a(result);
		cout << "Transation ok!" << result << endl;
	}
}



void _fail_rollback_call(unsigned int result)
{
	cout << "Trancation fail and rollback called." << endl;
}

void _success_submit_call(unsigned int result)
{
	cout << "Trancation success and submit called." << endl;
}

void _sequence(_do_sth a, ...)
{
	va_list ap;
	_do_sth do_it;
	va_start(ap, a);
	if (!a)
	{
		return;
	}

	if (!a())
	{
		_RESULTBITMAP |= 1;
	}
	else
	{
		_RESULTBITMAP |= (1 << 31);
		return;
	}

	do_it = va_arg(ap, _do_sth);
	if (!do_it)
	{
		va_end(ap);
		return;
	}
	if (!do_it())
	{
		_RESULTBITMAP |= (1 << 1);
	}
	else
	{
		_RESULTBITMAP |= (1 << 31);
		return;
	}

	do_it = va_arg(ap, _do_sth);
	if (!do_it)
	{
		va_end(ap);
		return;
	}
	if (!do_it())
	{
		_RESULTBITMAP |= (1 << 2);
	}
	else
	{
		_RESULTBITMAP |= (1 << 31);
		return;
	}

	do_it = va_arg(ap, _do_sth);
	if (!do_it)
	{
		va_end(ap);
		return;
	}
	if (!do_it())
	{
		_RESULTBITMAP |= (1 << 3);
	}
	else
	{
		_RESULTBITMAP |= (1 << 31);
		return;
	}

	do_it = va_arg(ap, _do_sth);
	if (!do_it)
	{
		va_end(ap);
		return;
	}
	if (!do_it())
	{
		_RESULTBITMAP |= (1 << 4);
	}
	else
	{
		_RESULTBITMAP |= (1 << 31);
		return;
	}


	do_it = va_arg(ap, _do_sth);
	if (!do_it)
	{
		va_end(ap);
		return;
	}
	if (!do_it())
	{
		_RESULTBITMAP |= (1 << 5);
	}
	else
	{
		_RESULTBITMAP |= (1 << 31);
		return;
	}

	do_it = va_arg(ap, _do_sth);
	if (!do_it)
	{
		va_end(ap);
		return;
	}

	if (!do_it())
	{
		_RESULTBITMAP |= (1 << 6);
	}
	else
	{
		_RESULTBITMAP |= (1 << 31);
		return;
	}

	va_end(ap);
	cout << "Sequence do!" << endl;
}