Constructing associative containers

Question

I was convinced (until I just tried it a moment ago) that it was possible to instantiate an associative container with array style notation.

For example,

std::set< int > _set = { 2, 3, 5 };

This isn't the case but I am wondering if there is any other way of bulk initialising a container in the constructor like this?

That should be possible in C++0x. As the language is currently, you can't initialize any container with this syntax. — visitor
– visitor, Commented Oct 22, 2010 at 11:00
@FredOverflow: According to the sgi documentation it is a sorted associative container. — Björn Pollex
– Björn Pollex, Commented Oct 22, 2010 at 14:18
@Arun: I always thought that an associative container provides a mapping from keys to elements, such as std::map<K, V> (each key is associated with its value). — fredoverflow
– fredoverflow, Commented Oct 22, 2010 at 14:37

Björn Pollex · Accepted Answer · 2010-10-22 09:42:41Z

2

You can use Boost.Assign.

std::set< int > _set = boost::assign::list_of(2)(3)(5);

answered Oct 22, 2010 at 9:42

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Comments

Oliver Charlesworth · Accepted Answer · 2010-10-22 09:43:49Z

0

You could do:

const int x[] = { 2, 3, 5 }; std::set<int> _set(&x[0], &x[sizeof(x)/sizeof(x[0])]);

!

answered Oct 22, 2010 at 9:43

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