Re: [Boost-users] multi_index:iterator_to complexity

Subject: Re: [Boost-users] multi_index:iterator_to complexity
From: Joaquin M Lopez Munoz (joaquin_at_[hidden])
Date: 2015-03-09 09:34:15

Matwey V. Kornilov <matwey.kornilov <at> gmail.com> writes:

> 09.03.2015 10:02, Joaquin M Lopez Munoz пишет:
> > 
> > iterator_to does not do any kind of search based on x, but takes a
> > reference to an element of the container and returns an iterator to
> > it (roughly speaking, converts an element pointer to a node pointer).
> >  [...]
> 
> As far as I understand, there should be some pointer magic, like the
> following
> 
> struct node {
> 	T obj;
> 	... // Rest
> };
> 
> so given x, (node*)&x will point to the struct enveloping the object and
> should provide access to index-specific data to allow iterator
> incrementation and dereferencing. What kind of additional data is stored
> in node?

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