1 -*- Autoconf -*- 2 3# Common code for C-like languages (C, C++, Java, etc.) 4 5# Copyright (C) 2012 Free Software Foundation, Inc. 6 7# This program is free software: you can redistribute it and/or modify 8# it under the terms of the GNU General Public License as published by 9# the Free Software Foundation, either version 3 of the License, or 10# (at your option) any later version. 11# 12# This program is distributed in the hope that it will be useful, 13# but WITHOUT ANY WARRANTY; without even the implied warranty of 14# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15# GNU General Public License for more details. 16# 17# You should have received a copy of the GNU General Public License 18# along with this program. If not, see <http://www.gnu.org/licenses/>. 19 20# b4_dollar_dollar_(VALUE, FIELD, DEFAULT-FIELD) 21# ---------------------------------------------- 22# If FIELD (or DEFAULT-FIELD) is non-null, return "VALUE.FIELD", 23# otherwise just VALUE. Be sure to pass "(VALUE)" is VALUE is a 24# pointer. 25m4_define([b4_dollar_dollar_], 26[m4_if([$2], [[]], 27 [m4_ifval([$3], [($1.$3)], 28 [$1])], 29 [($1.$2)])]) 30 31# b4_dollar_pushdef(VALUE-POINTER, DEFAULT-FIELD, LOCATION) 32# b4_dollar_popdef 33# --------------------------------------------------------- 34# Define b4_dollar_dollar for VALUE and DEFAULT-FIELD, 35# and b4_at_dollar for LOCATION. 36m4_define([b4_dollar_pushdef], 37[m4_pushdef([b4_dollar_dollar], 38 [b4_dollar_dollar_([$1], m4_dquote($][1), [$2])])dnl 39m4_pushdef([b4_at_dollar], [$3])dnl 40]) 41m4_define([b4_dollar_popdef], 42[m4_popdef([b4_at_dollar])dnl 43m4_popdef([b4_dollar_dollar])dnl 44]) 45