如何获取std :: list <std::string> :: iterator输出错误值？

Question

I'm searching through a list of values, and want to have it return some sort of 'default' error value when it cant find the value to search for. I don't mean std::cerr . i mean a value that i can use in my program like a bool. However, if it does find the string, I need the pointer value of where it is in the string. How do I do this?

Answer 1

typedef std::list<std::string> MyList;
MyList  mylist;
MyList::iterator iter = mylist.find("somestring");
if (iter != mylist.end() ) {
   // the string was found
} else {
   // the string was not found
}

Answer 2

The idiomatic way is to return an iterator (not a pointer), and return the end iterator when the element was not found.

But you don't need to write this, because <algorithm> already contains std::find .