Re: [Boost-users] BGL problem, originally [Another C++inheritence/polymorphism problem]

From: Douglas Gregor (dgregor_at_[hidden])
Date: 2005-02-13 16:58:30

On Feb 12, 2005, at 8:48 PM, Welson Sun wrote:
> Thanks, you are right. Now both the vertex property writer and edge 
> property
> writer works.

Great!

> But I don't understand why "reference" will cause this problem? Isn't 
> it
> just an alias of an object?

It's a C++ quirk... when you have a temporary value, you can't pass it 
to a non-const reference. The intent is to help you avoid accidentally 
making changes to a temporary that will never be seen elsewhere, but 
sometimes it's a little weird.

        Doug