Text + variable in qDebug

Question

I want to combine text and variable in qDebug:

QString city_name = "London";
qDebug() << QString("You choose CITY:").arg(city_name);

It doesn't work and i don't know why. Error is:

QString::arg: Argument missing: You choose CITY:, ?????

Answer 1

Add %1:

QString city_name = "London";
qDebug() << QString("You choose CITY: %1").arg(city_name);