[Boost-users] Re: Lambda question (deferring evaluation)

"Peter Dimov" <pdimov@mmltd.net> wrote in message news:006101c51ff2$f5868e30$6501a8c0@pdimov2...

Johan Nilsson wrote:

[...]

...

std::vector<shared_ptr<Foo> > foos(10); std::for_each(foos.begin(), foos.end(), _1 = shared_ptr<Foo>(new Foo));

Lambda way (according to the docs, I haven't tried it):

std::for_each( foos.begin(), foos.end(), _1 = bind( constructor< shared_ptr<Foo> >(), new_ptr<Foo>() ) );

(probably leaks when new throws)

Old school way:

shared_ptr<Foo> createFoo() { return shared_ptr<Foo>( new Foo ); }

std::generate( foos.begin(), foos.end(), createFoo );

here is also BOOST_FOREACH way: BOOST_FOREACH( shared_ptr<Foo>&, elem, foos ) elem.reset( new Foo ); Gennadiy