1 # =========================================================================== 2 # http://www.gnu.org/software/autoconf-archive/ax_prog_flex.html 3 # =========================================================================== 4 # 5 # SYNOPSIS 6 # 7 # AX_PROG_FLEX(ACTION-IF-TRUE,ACTION-IF-FALSE) 8 # 9 # DESCRIPTION 10 # 11 # Check whether flex is the scanner generator. Run ACTION-IF-TRUE if 12 # successful, ACTION-IF-FALSE otherwise 13 # 14 # LICENSE 15 # 16 # Copyright (c) 2009 Francesco Salvestrini <salvestrini (a] users.sourceforge.net> 17 # Copyright (c) 2010 Diego Elio Petteno` <flameeyes (a] gmail.com> 18 # 19 # This program is free software; you can redistribute it and/or modify it 20 # under the terms of the GNU General Public License as published by the 21 # Free Software Foundation; either version 2 of the License, or (at your 22 # option) any later version. 23 # 24 # This program is distributed in the hope that it will be useful, but 25 # WITHOUT ANY WARRANTY; without even the implied warranty of 26 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General 27 # Public License for more details. 28 # 29 # You should have received a copy of the GNU General Public License along 30 # with this program. If not, see <http://www.gnu.org/licenses/>. 31 # 32 # As a special exception, the respective Autoconf Macro's copyright owner 33 # gives unlimited permission to copy, distribute and modify the configure 34 # scripts that are the output of Autoconf when processing the Macro. You 35 # need not follow the terms of the GNU General Public License when using 36 # or distributing such scripts, even though portions of the text of the 37 # Macro appear in them. The GNU General Public License (GPL) does govern 38 # all other use of the material that constitutes the Autoconf Macro. 39 # 40 # This special exception to the GPL applies to versions of the Autoconf 41 # Macro released by the Autoconf Archive. When you make and distribute a 42 # modified version of the Autoconf Macro, you may extend this special 43 # exception to the GPL to apply to your modified version as well. 44 45 #serial 12 46 47 # mattst88: 48 # Replaced m4_ifnblank(...) with m4_ifval(m4_normalize(...), ...) 49 # since m4_ifnblank requires autoconf-2.64. 50 51 AC_DEFUN([AX_PROG_FLEX], [ 52 AC_REQUIRE([AM_PROG_LEX]) 53 AC_REQUIRE([AC_PROG_EGREP]) 54 55 AC_CACHE_CHECK([if flex is the lexer generator],[ax_cv_prog_flex],[ 56 AS_IF([$LEX --version 2>/dev/null | $EGREP -qw '^g?flex'], 57 [ax_cv_prog_flex=yes], [ax_cv_prog_flex=no]) 58 ]) 59 AS_IF([test "$ax_cv_prog_flex" = "yes"], 60 m4_ifval(m4_normalize([$1]), [[$1]]), 61 m4_ifval(m4_normalize([$2]), [[$2]]) 62 ) 63 ]) 64
