1 
2 // Copyright (C) 2009-2012 Lorenzo Caminiti
3 // Distributed under the Boost Software License, Version 1.0
4 // (see accompanying file LICENSE_1_0.txt or a copy at
5 // http://www.boost.org/LICENSE_1_0.txt)
6 // Home at http://www.boost.org/libs/local_function
7 
8 #include <boost/local_function.hpp>
9 #include <boost/preprocessor/cat.hpp>
10 #include <boost/detail/lightweight_test.hpp>
11 #include <iostream>
12 
13 #define LOCAL_INC_DEC(offset) \
14     int BOOST_LOCAL_FUNCTION_ID(BOOST_PP_CAT(inc, __LINE__), /* unique ID */ \
15             (const bind offset) (const int x) ) { \
16         return x + offset; \
17     } BOOST_LOCAL_FUNCTION_NAME(inc) \
18     \
19     int BOOST_LOCAL_FUNCTION_ID(BOOST_PP_CAT(dec, __LINE__), \
20             (const bind offset) (const int x) ) { \
21         return x - offset; \
22     } BOOST_LOCAL_FUNCTION_NAME(dec)
23 
24 #define LOCAL_INC_DEC_TPL(offset) \
25     T BOOST_LOCAL_FUNCTION_ID_TPL(BOOST_PP_CAT(inc, __LINE__), \
26             (const bind offset) (const T x) ) { \
27         return x + offset; \
28     } BOOST_LOCAL_FUNCTION_NAME_TPL(inc) \
29     \
30     T BOOST_LOCAL_FUNCTION_ID_TPL(BOOST_PP_CAT(dec, __LINE__), \
31             (const bind offset) (const T x) ) { \
32         return x - offset; \
33     } BOOST_LOCAL_FUNCTION_NAME_TPL(dec)
34 
35 template<typename T>
f(T & delta)36 void f(T& delta) {
37     LOCAL_INC_DEC_TPL(delta) // Multiple local functions on same line.
38     BOOST_TEST(dec(inc(123)) == 123);
39 }
40 
main(void)41 int main(void) {
42     int delta = 10;
43     LOCAL_INC_DEC(delta) // Declare local functions on same line using `_ID`.
44     BOOST_TEST(dec(inc(123)) == 123);
45     f(delta);
46     return boost::report_errors();
47 }
48 
49