The BOOST_PP_LIST_TRANSFORM_D macro transforms each element in a list according to a supplied transformation.
It reenters BOOST_PP_WHILE with maximum efficiency.
Usage
BOOST_PP_LIST_TRANSFORM_D(d, op, data, list)
Arguments
- d
-
The next available BOOST_PP_WHILE iteration.
- op
-
A ternary predicate of the form op(d, data, elem).
This transformation is expanded by BOOST_PP_LIST_TRANSFORM for each element in list with the next available BOOST_PP_WHILE iteration,
the auxiliary data, and the current element in list.
- data
-
Auxiliary data passed to pred.
- list
-
The list to be transformed.
Remarks
This macro expands
op for each element in
list.
It builds a new
list out of the results of each call.
If, for example,
list is (
a, (
b, (
c,
BOOST_PP_NIL))),
this macro expands to...
(op(d, data, a), (op(d, data, b), (op(d, data, c), BOOST_PP_NIL)))
See Also
Requirements
Sample Code
#include <boost/preprocessor/arithmetic/inc.hpp>
#include <boost/preprocessor/list/fold_right.hpp>
#include <boost/preprocessor/list/transform.hpp>
#define A (1, (2, (3, (4, BOOST_PP_NIL))))
#define B (A, (A, (A, (A, BOOST_PP_NIL))))
#define OP_T(d, data, x) BOOST_PP_INC(x)
#define OP(d, state, x) (BOOST_PP_LIST_TRANSFORM_D(d, OP_T, 2, x), state)
BOOST_PP_LIST_FOLD_RIGHT(OP, BOOST_PP_NIL, B)
/*
expands to:
((2, (3, (4, (5, BOOST_PP_NIL)))), ((2, (3, (4, (5, BOOST_PP_NIL)))),
((2, (3, (4, (5, BOOST_PP_NIL)))), ((2, (3, (4, (5, BOOST_PP_NIL)))),
BOOST_PP_NIL))))
*/