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From: gcc@integrable-solutions.net (Gabriel Dos Reis)
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Subject: =?iso-8859-15?q?Re:_Problems_interpreting_requirement_for_std::?=
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AlbertoBarbati@libero.it (Alberto Ganesh Barbati) writes:

| kanze wrote:
| > 
| > Finally, what about something like:
| > 
| >     copy( l.begin(), l.end(), back_inserter( l ) ) ;
| > 
| > I think that, realistically, this will generally result in an
| > endless loop.  And yet, it requires quite a stretch of the
| > imagination to say that back_inserter( l ) is in the range of
| > [l.begin(),l.end()).
| 
| It doesn't result in an endless loop, because l.end() is not
| re-evaluated during the execution of copy.

the "because" part is irrelevant.  See below.

And James' claim that the l.end() is invalidated is bogus.

| The value which is passed as
| the "last" parameter remains a valid iterator which keeps pointing to
| the same element for the whole execution of the algorithm. Therefore the
| statement will effectively just append a entire copy of l at the end of
| l itself.

Consider this:

    p = l.end();
    l.push_back(8);
    q = l.end();
    assert (p == q);

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