Need your help to explain this OOP

[jaden5165]

_v3signal *_v3main :: find_v3_signal_bylhs ( char *s )
{
printf("chunhaun:lhs1,%s,%d\n",s,_num_v3_signals);
	if(!s){
printf("chunhaun:checklhs\n");
		return NULL;
	}

	for (int i = 0; i < _num_v3_signals; i++)
	{
		if (!strcmp (_V3Signals[i]->get_lhs (), s)){
cout << "chunhaun:lhs3," << _V3Signals[i] <<endl;
			return _V3Signals[i];
		}
	}
printf("chunhaun:lhsreturn\n");
	return NULL;
}

May I know when return _V3Signals[i];,what is the content actually stored inside _V3Signals[i]? What chapter should I study to know more on this?I am confuse.

For simple example:
int Class::add(a,b)
{
return a+b
}


I will know that the return content will be an integer value.But for the code above _v3signal *_v3main :: find_v3_signal_bylhs ( char *s )
So i dont know what actually will be return and stored inside _V3Signals[i];

[Aceix]

There is a syntax for a function prototype, which is:
<return type> <function name>(<parameters>);
So in the code above, the function would be returning a pointer to _v3signal.

More info: http://cplusplus.com/doc/tutorial/functions/

Aceix.

[keskiverto]

Furthermore, the _V3Signals must have been declared somewhere. Perhaps in description of class _v3main? (_V3Signals[i] does not need to be _v3signal * as long as it is convertible to that type.)

Btw, line 3 is in wrong place. It does use s. s could be null. Only after the if-clause on lines 4-7 does one know that s is not null and can be used.

Also note that prefix and suffix underscores on names might cause trouble, because some compilers use them in their internal implementation.