#include <boost/bit_logic/bit_container_type.hpp>
  PackT unpack <PackT> ( size_type upper_bit_idx, size_type lower_bit_idx ) ;
  PackT unpack <PackT,EncodingT> ( size_type upper_bit_idx, size_type lower_bit_idx ) ;

PackT		Any Integral type e.x. enum, unsigned long, int
EncodingT	signed_magnitude ones_complement twos_complement	This is for specifying signed numbers binary encoding. see Signed Integrals

Note: These functions are equivelant for all bit_container types. bit_array<N>, bit_vector, bit_container_adaptor

Unpack function decodes a series of bits within a Bit Container as a given type and returns it.

TODO: Make this not look exactly like pack or merge them.

For example:

 bit_array<10> a ; 
 enum color { red = 0, green = 1, blue = 2, pink = 22 } ; 
 a.unpack( red, 1, 0 ); 
 color my_color = a.ununpack<color> ( 1, 0);

This above code allows for an enumerated type to be represented in 2 bits. The value 0 can be represented by 2 bits, and

 v.unpack( pink, 2, 0); 

This code throws an exception as the binary value of 22 : 10110 requires a minimum of 5 bits to be represented fully. This container adheres to the strict guarantee and no data within v has been harmed by the attempt to unpack data that would overflow into it.

 uint32_t my_uint = 42 ; /// 101010 binary representation
 a.unpack( my_uint, 8, 3 ) ; 
 uint32_t another_uint = a.ununpack>uint32_t< (9,3); 

This code unpacks the 32 bit unsigned integral type of value 42 into the most significant 7 bits of a. The value requires a minmum of 6 bits to be precisely represented within that bit range.

Signed integral bit representation within a bit_container is defaulted to 2's complement.

 int32_t my_int = -1 ;
 a.unpack( my_int, 8, 0 ) ; 
 cout << a << endl ;

This will print out :

 111111111

 a.unpack<signed_magnitude>( my_int, 8, 0 ) ; 
 cout << a << endl ;

This will print out :

 100000001

unpack can throw any of the following exceptions.

std::logic_error	Backwards ordering of range selection or 0 sized type assignment
bit_logic::bit_out_of_bounds	Bit Index exceeds boundaries of container