...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
detail/for.m4 provides BOOST_M4_FOR, an m4 macro that provides the equivalent of a #for preprocessor instruction.
This macro must be used by an m4 file. This file assumes that the option -P is used, to force an m4_ prefix on all builtin symbols.
If called with the wrong number of arguments (less than 4 or more than 5), BOOST_M4_FOR will exit with an error. If the starting value ($2) is greater than or equal to the ending value ($3), BOOST_M4_FOR will do nothing. Otherwise, it will repeat the text ($4), binding the variable ($1) to the values in the range [starting value ($2), ending value ($3)), and repeat the delimeter text ($5) in-between each occurrence of the repeat text ($4).
Note of the quotation marks (") used in the table below are in the input or output; they are shown to delimit whitespace. All code within a pair of quotation marks is intended to be on one line.
Input | Output |
---|---|
"BOOST_M4_FOR(i, 1, 3)" | Boost m4 script: BOOST_M4_FOR: Wrong number of arguments (3) |
"BOOST_M4_FOR(i, 1, 3, i, ` ', 13)" | Boost m4 script: BOOST_M4_FOR: Wrong number of arguments (6) |
"BOOST_M4_FOR(i, 7, 0, i )" | (nothing) |
"BOOST_M4_FOR(i, 0, 0, i )" | (nothing) |
"BOOST_M4_FOR(i, 0, 7, i )" | "0 1 2 3 4 5 6 " |
"BOOST_M4_FOR(i, -13, -10, i )" | "-13 -12 -11 " |
"BOOST_M4_FOR(i, 0, 8, BOOST_M4_FOR(j, 0, 4, (i, j)
)" ")" |
"(0, 0) (0, 1) (0, 2) (0, 3) " "(1, 0) (1, 1) (1, 2) (1, 3) " "(2, 0) (2, 1) (2, 2) (2, 3) " "(3, 0) (3, 1) (3, 2) (3, 3) " "(4, 0) (4, 1) (4, 2) (4, 3) " "(5, 0) (5, 1) (5, 2) (5, 3) " "(6, 0) (6, 1) (6, 2) (6, 3) " "(7, 0) (7, 1) (7, 2) (7, 3) " "" |
"BOOST_M4_FOR(i, 7, 0, i, |)" | (nothing) |
"BOOST_M4_FOR(i, 0, 0, i, |)" | (nothing) |
"BOOST_M4_FOR(i, 0, 7, i, |)" | "0|1|2|3|4|5|6" |
"BOOST_M4_FOR(i, -13, -10, i, `, ')" | "-13, -12, -11" |
"BOOST_M4_FOR(i, 0, 8, `[BOOST_M4_FOR(j, 0, 4, (i, j),
`, ')]', `," "')" |
"[(0, 0), (0, 1), (0, 2), (0, 3)]," "[(1, 0), (1, 1), (1, 2), (1, 3)]," "[(2, 0), (2, 1), (2, 2), (2, 3)]," "[(3, 0), (3, 1), (3, 2), (3, 3)]," "[(4, 0), (4, 1), (4, 2), (4, 3)]," "[(5, 0), (5, 1), (5, 2), (5, 3)]," "[(6, 0), (6, 1), (6, 2), (6, 3)]," "[(7, 0), (7, 1), (7, 2), (7, 3)]" |
Revised 05 December, 2006
Copyright © 2000, 2001 Stephen Cleary (scleary AT jerviswebb DOT com)
Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)