The BOOST_PP_LIST_AT macro extracts an element in a list.

Usage

BOOST_PP_LIST_AT(list, index)

Arguments

list
The list from which a element is to be extracted.  This list must have at least index + 1 elements.
index
The zero-based position in the list of the element to be extracted.

Remarks

Previously, this macro could not be used inside BOOST_PP_WHILE.  There is no longer any such restriction.  It is more efficient, however, to use BOOST_PP_LIST_AT_D in such a situation.

See Also

Requirements

Header:  <boost/preprocessor/list/at.hpp>

Sample Code

#include <boost/preprocessor/list/at.hpp>

#define LIST (a, (b, (c, BOOST_PP_NIL)))

BOOST_PP_LIST_AT(LIST, 0) // expands to a
BOOST_PP_LIST_AT(LIST, 2) // expands to c

Copyright Housemarque Oy 2002
Copyright Paul Mensonides 2002

Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at www.boost.org/LICENSE_1_0.txt)