Return a reference to object from function, and modify the (original) object which is in a std::list

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I'm not used to C++. I'm trying to find (via a function), then manipulate values inside an object that is in a std::list

Can anybody help? Thanks.

C++

MyObject getObjectByMyValue(MyValue value)
{
	for (MyObject object : _objects)
        {
		if (object.value == value)
		{
			return object;
		}
	}
	throw("");
}

void otherFunction()
{
	try
	{
		MyObject& object = getObjectByMyValue("something");
		object.someValue = "something else"; // it doesn't change the value
	}
	catch (...)
	{
		//object not found
	}
}

What I have tried:

I've tried using pointers and returning NULL when it isn't found also, but that doesn't work.

I also understand that return object; reference may be out of scope here by the time the other function gets it.

I've tried Googling and found examples where people use new to create another object, but I don't want to do that if possible.

Posted 31-May-16 11:10am

xxhatred

Updated 31-May-16 12:06pm

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nv3 · Accepted Answer · 2016-05-31T12:06:00

Use a reference to MyObject in your for loop:

C++

for (MyObject& object : _objects)

That avoids the problem with the object variable going out of scope.

But allow me the remark that it is usually not a good practice to throw an exception for a "not found" condition. This makes your code more difficult to use and causes unnecessary headaches for a rather common situation. Your approach returning a pointer and NULL in the case that the object has not been found is probably better. And with the above correction of the for loop it will work.