String class question

[Ulnarian]

Say I have the following code:



string dog;
char cat;
cin >> cat;

if (dog.find(cat)!=string::npos)
cout << "Yup, " << cat << " is in the dog string";



I know what the code does, however, I'm a bit fuzzy on why the if statement would return either true or false. Could anyone explain the string::npos thing to a newb like me (my book is a bit vague on the subject).

Thanks

[laserlight]

The various find() member functions of std::string return the index of (the first character of) the matching portion of the string, and std::string::npos if it is not found. So, if the return value is not equal to std::string::npos then there must have been a match.

[Ulnarian]

Ah, thanks