SOLVED: error: no match for ‘operator=’

johnmerlino

I am getting the following error:

/home/myuser/program/MyGateway/protocol/iridium/mailbox.cpp: In member function ‘QList<InmarsatMessage> IridiumMailbox::getInmarsatMessages()’:
/home/myuser/program/MyGateway/protocol/iridium/mailbox.cpp:171:54: error: no match for ‘operator=’ in ‘msg.InmarsatMessage::time = inmarsat_time.QDateTime::setTimeSpec((Qt::TimeSpec)1u)’
/home/myuser/program/MyGateway/protocol/iridium/mailbox.cpp:171:54: note: candidate is:
/usr/include/qt4/QtCore/qdatetime.h:225:16: note: QDateTime& QDateTime::operator=(const QDateTime&)
/usr/include/qt4/QtCore/qdatetime.h:225:16: note: no known conversion for argument 1 from ‘void’ to ‘const QDateTime&’

It's about this line of code right here:

QDateTime inmarsat_time = QDateTime::fromString(message->received().toString(), "ddd MMM d HH:mm:ss yyyy");

That function received() is here:

QDateTime ImapMessage::received (void) const {
return(d->received);
}

Any idea why I am getting this error?

JKSH

Hi,

Your error line is
@
msg.InmarsatMessage::time = inmarsat_time.QDateTime::setTimeSpec((Qt::TimeSpec)1u)
@

That's not valid C++. What is your goal here?

[quote]
@
QDateTime inmarsat_time = QDateTime::fromString(message->received().toString(), “ddd MMM d HH:mm:ss yyyy”);
@
[/quote]This line is valid. But why do you convert a QDateTime to QString, and then convert it back to QDateTime again?

johnmerlino

But there is no line of code as such:

msg.InmarsatMessage::time = inmarsat_time.QDateTime::setTimeSpec((Qt::TimeSpec)1u)

That error is pointing to this line of code:

QDateTime inmarsat_time = QDateTime::fromString(message->received().toString(), “ddd MMM d HH:mm:ss yyyy”);

koahnig

Please use "code wrappings":http://qt-project.org/wiki/ForumHelp#e3f82045ad0f480d3fb9e0ac2d58fb01 to structure your post.
Code wrappings improve reading of your code and error listing sections significantly.

JKSH

[quote]But there is no line of code as such:
msg.InmarsatMessage::time = inmarsat_time.QDateTime::setTimeSpec((Qt::TimeSpec)1u)[/quote]You're right; I didn't realize GCC expands code in its error messages.

[quote]That error is pointing to this line of code:
QDateTime inmarsat_time = QDateTime::fromString(message->received().toString(), “ddd MMM d HH:mm:ss yyyy”);[/quote]
Hmm, I can't see any errors in that line. What is your compiler version?

Anyway, why do you call toString() and then fromString() again? Just assign message->received() directly to inmarsat_time. Your code will be simpler, and the error might go away.

P.S. I agree with koahnig. Your code and errors were hard to read.

johnmerlino

So I was able to make the error go away by changing this:

@ QDateTime inmarsat_time = message->received();
msg.time = inmarsat_time.setTimeSpec(Qt::UTC);
@
to this:

@ QDateTime inmarsat_time = message->received();
msg.time.setTimeSpec(Qt::UTC);@

Why does the latter work and not the former?

JKSH

[quote]That error is pointing to this line of code:
QDateTime inmarsat_time = QDateTime::fromString(message->received().toString(), “ddd MMM d HH:mm:ss yyyy”);[/quote]The error was NOT pointing to the line above. It was pointing to this one:
[quote]
@msg.time = inmarsat_time.setTimeSpec(Qt::UTC);@
[/quote]setTimeSpec() returns void. You can't assign void to msg.time

johnmerlino

ok didn't realize setTimeSpec() returned void.