SC_METHOD use next_tirgger() delay time once like SC_THREAD use wait()

[Allen yang]

I have these  code. And I want to execute it once print timestamp with SC_METHOD.

But if I use next_trigger in the register function Push, it will print many time not once.

SC_THREAD use wait()

```

class TestPlatform : public sc_module
{
    public:
        SC_HAS_PROCESS(TestPlatform);
        TestPlatform(const sc_module_name& name, const int freq) : sc_module(name), 
        {
            SC_THREAD(Push);
        };
    
    void Push();
    bool m_trigger_flag;

};

void TestPlatform::Push()
{
    wait(2, SC_NS);

    cout << sc_time_stamp() << endl;
}

```

SC_METHOD use next_trigger implement.  I use a memeber var m_trigger_flag to control it execute once. I wonder there is any better implement.

```

class TestPlatform : public sc_module
{
    public:
        SC_HAS_PROCESS(TestPlatform);
        TestPlatform(const sc_module_name& name, const int freq) : sc_module(name), 
        {
            SC_METHOD(Push);
        };
    
    void Push();
    bool m_trigger_flag;

};

void TestPlatform::Push()
{
    if (m_trigger_flag) {
        next_trigger(2, SC_NS);
        m_trigger_flag = false;
        return;
    }

    cout << sc_time_stamp() << endl;
}

```

[Eyck]

When posting code it is best to show an example using https://www.edaplayground.com. I copied part of ypur code at https://www.edaplayground.com/x/NSAs

The problem is the missing initialization of m_trigger_flag. Depending of your build settings and many more factors it might be true or false. When being false the method is only executed during the initial evalauation phase....

[Allen yang]

Thanks @Eyck. I have copy your edaplaygroud code to myself at https://www.edaplayground.com/x/7yHV. And I can run sc_method with next_trigger in 2ns only. 

I find that using the var m_trigger_flag to control delay execution on sc_mehtod register function is ugly. Is there any better way to implete like sc_thread using wait(). 

[Eyck]

If I got you rigth you want to trigger the method exactly once after 2ns, right?

In that case I would write the TestPlatform differently:

class TestPlatform : public sc_core::sc_module {
public:
    SC_HAS_PROCESS(TestPlatform);
    TestPlatform(const sc_core::sc_module_name& name, const int freq) : sc_core::sc_module(name), m_trigger_flag(true) {
        SC_METHOD(Push);
        dont_initialize();
        sensitive<<trigger_evt;
        trigger_evt.notify(sc_core::sc_time(2, sc_core::SC_NS));
    };
    void Push(){
        std::cout << sc_core::sc_time_stamp() << std::endl;
    } 
private:
    sc_core::sc_event trigger_evt;
};