ASSERT occurs on a.at(5).isNull()

rbmisc

Here is the code I'm trying:
#include <QTextStream>

int main(void)
{

QTextStream out(stdout);

QString a = "Eagle";

out << a[0] << endl;
out << a[4] << endl;

out << a.at(0) << endl;

if (a.at(5).isNull())
{
    out << "Outside the range of the string" << endl;
}

return 0;

}
Here is the output:
E
e
E
ASSERT: "uint(i) < uint(size())" in file ../../Qt/5.6/clang_64/lib/QtCore.framework/Headers/qstring.h, line 868

Isn't a.at(5).isNull() the correct coding?

Paul Colby

The assertion is expected behaviour for QString::at

The position must be a valid index position in the string (i.e., 0 <= position < size()).

Instead, you should do something like:

if (5 >= a.size())
{
    out << "Outside the range of the string" << endl;
}

Cheers.