Oh gosh.... how could I oversee THAT? >o<
Allright... now it works and I understand the difference.... Thank you >o<
-----Original Message-----
From: i.nix...@autistici.org <i.nix...@autistici.org>
Sent: 21 October 2020 16:55
To: boost-users@lists.boost.org
Cc: Gaier, Bjoern <bjoern.ga...@horiba.com>
Subject: Re: [Boost-users] [Newbie][Intrusive] - Beginners question
On 2020-10-21 14:33, Gaier, Bjoern via Boost-users wrote:
> Hey everybody,
>
> I looked into the boost intrusive container and played around with it
> a bit. I tried the following code:
> struct animal : public boost::intrusive::list_base_hook<>
> {
> std::string name;
> int legs;
>
> animal(std::string n, int l) : name{std::move(n)},
> legs{l} {} };
>
> int main(int argc, char **argv)
> {
> std::vector<animal> test;
> boost::intrusive::list<animal> wuff;
>
> for(int n = 0; n < 5; n++)
> {
> test.push_back(animal("Katze", 4));
> }
>
> for(int n = 0; n < 5; n++)
> {
> wuff.push_back(test[n]);
> }
>
because `test` has 5 elems:
> for(int n = 0; n < 15; n++)
> <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
> {
> wuff.push_back(test[n]);
> }
>
> for(auto elem : wuff)
> {
> printf("%s\n", elem.name.c_str());
> }
> }
>
> This code does crash! I guess this is because "test" relocated the
> memory and therefor "wuff" lost its references. I would expect the
> same result if I would have a std::list with pointers to animal
> structures - this is why I wonder what the benefit of an intrusive
> container is compared to the same container with just pointers in it.
>
> Hope someone can explain me this! Thank you in advance and kind
> greetings Björn Als GmbH eingetragen im Handelsregister Bad Homburg
> v.d.H. HRB 9816, USt.ID-Nr. DE 114 165 789 Geschäftsführer: Dr.
> Hiroshi Nakamura, Dr.
> Robert Plank, Markus Bode, Heiko Lampert, Takashi Nagano, Junichi
> Tajika, Ergin Cansiz.
>
> _______________________________________________
> Boost-users mailing list
> Boost-users@lists.boost.org
> https://lists.boost.org/mailman/listinfo.cgi/boost-users
Als GmbH eingetragen im Handelsregister Bad Homburg v.d.H. HRB 9816, USt.ID-Nr.
DE 114 165 789 Geschäftsführer: Dr. Hiroshi Nakamura, Dr. Robert Plank, Markus
Bode, Heiko Lampert, Takashi Nagano, Junichi Tajika, Ergin Cansiz.
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