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Binary Integer Literals

Introduction
Example
Reference
Acknowledgments

The macro BOOST_BINARY is used for the representation of binary literals. It takes as an argument a binary number arranged as an arbitrary amount of 1s and 0s in groupings of length 1 to 8, with groups separated by spaces. The macro serves as a replacement for binary integer literals, adopted in C++14.

The type of the literal yielded is determined by the same rules as those of hex and octal literals. By implementation, this macro expands directly to an octal literal during preprocessing, so there is no overhead at runtime and the result is usable in any place that an octal literal would be.

In order to directly support binary literals with suffixes, additional macros of the form BOOST_BINARY_XXX are also provided, where XXX is a standard integer suffix in all capital letters.

In addition, LL and ULL suffixes may be used for representing long long and unsigned long long types in compilers which provide them as an extension.

The BOOST_BINARY family of macros resides in the header <boost/utility/binary.hpp>.

void foo( int );

void foo( unsigned long );

void bar()
{
  int value1 = BOOST_BINARY( 100 111000 01 1 110 );

  unsigned long value2 = BOOST_BINARY_UL( 100 001 ); // unsigned long

  long long value3 = BOOST_BINARY_LL( 11 000 ); // long long if supported

  assert(    BOOST_BINARY( 10010 )
          &  BOOST_BINARY( 11000 )
          == BOOST_BINARY( 10000 )
        );

  foo( BOOST_BINARY( 1010 ) ); // calls the first foo

  foo( BOOST_BINARY_LU( 1010 ) ); // calls the second foo
}

Reference


BOOST_BINARY(bit_groupings)
BOOST_BINARY_U(bit_groupings)
BOOST_BINARY_L(bit_groupings)
BOOST_BINARY_UL(bit_groupings)
BOOST_BINARY_LU(bit_groupings)
BOOST_BINARY_LL(bit_groupings)
BOOST_BINARY_ULL(bit_groupings)
BOOST_BINARY_LLU(bit_groupings)
BOOST_SUFFIXED_BINARY_LITERAL(bit_groupings, suffix)
BOOST_SUFFIXED_BINARY_LITERAL_D(d, bit_groupings, suffix)
BOOST_BINARY_LITERAL_D(d, bit_groupings)

Contributed by Matt Calabrese.


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