Invisible <voi### [at] devnull> wrote:
> I see. (I think!) So, presumably, when you copy std::vector "by value", 
> all it's actually copying is the reference to the real data?

  Actually, when you assign an std::vector object to another, whether it
performs a deep-copy of the data or if it uses some copy-on-write mechanism
to perform lazy copying depends on the library implementation, but AFAIK
most if not all library implementations use deep-copying.

  Thus, if you assign one std::vector object to another, all the data it
contains will be copied as well.

  Of course if you want copy-on-write instead, then you can create your own
"vector" which does that. (I have actually done precisely this for some
projects because of the benefits of this technique.)

-- 
                                                          - Warp

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