Function isNumeric

kdevplatform/project/projectmodel.cpp:715–724

static const int maximumCacheExtensionLength = 3;

bool isNumeric(QStringView str)
{
    if (str.isEmpty()) {
        return false;
    }

    return std::all_of(str.begin(), str.end(), [](const QChar c) {
        return c.isNumber();
    });
}

class IconNameCache
{