Re: [Boost-users] boost:array lacks a statically-checked get()

5 Jun 2007


      On 6/5/07, Benoit Hudson  wrote:
...
On 6/4/07, Chris Weed  wrote:
...
On 6/3/07, Benoit Hudson  wrote:
...
Reading the archives, I see that the idea of adding a
  template <unsigned i> T get();
function to boost::array has been somewhat summarily rejected as unnecessary:
  http://lists.boost.org/boost-users/2005/08/12983.php
et seq.
And yet I'm finding myself wanting it repeatedly.  Here are three
places I've seen it crop up:
Isn't this functionality available using the boost::fusion extension
for array? You might want to take a look at boost::fusion.
Chris
Doesn't appear to.  The following compiles against CVS of 5 minutes
ago, without error:
#include 
#include 
#include 
boost::array arr = {{ 1, 2, 3}};
int x() {
  // arr[4]
  return boost::fusion::at_c<4>(arr);
}
It compiles down to a call to __assert_fail, which is the same
behaviour as just using arr[4].
Following all the #includes and templates, I guess it's that
boost/fusion/sequence/adapted/array/detail/at_impl.hpp lines 36-40
should probably have a BOOST_STATIC_ASSERT in there?

-- Benoît