c++ – How do I apply STL algorithms in Qt?

Question:

How to apply STL algorithms in Qt, for example QStringList and set_difference , for example? If it is possible of course.

Answer:

All container containers have begin() and end() methods (as well as cbegin() etc.) that return STL-compatible iterators; they also have QList , which QStringList . They should be passed to STL functions of generalized algorithms.

QSet<QString> strongWords{"криворучкие", "дураки", /*...*/};

//....
QString userOpinion = getUserOpinion();
QStringList userOpinionWords = qSort(userOpinion.split(QRegExp("\\s+")'));

QStrinList inapropriateWords;

std::set_difference(userOpinionWords.cbegin(), userOpinionWords.cend()
                    strongWords.cbegin(), strongWords.cend(),
                    std::inserter(inapropriateWords, inapropriateWords.begin()));

if (!inapropriateWords.isEmpty()) {
    QMessageBox::info (QString ("Ваш отзыв очень важен для нас, но следующие слова неприемлимы: ").append(inapropriateWords.join(", ")));
    throw std::runtime_error ("Пользователь был груб, поэтому мы бросим исключение и не будем его ловить.");
}

You also need to remember that, at its core, std::set_difference() accepts ordered containers as input …