我想问一些问题，这是我的代码
configure.ac我的输入## Process this file with autoconf to produce a configure script.
##
## Configure.ac for RcppSBML
##
## Copyright (C) 2010 Romain Francois and Dirk Eddelbuettel
## Copyright (C) 2014 - 2015 Dirk Eddelbuettel
##
## Licensed under GNU GPL 2 or later
# The version set here will propagate to other files from here
AC_INIT([Rcppsbml], 0.1.0)
# Checks for common programs using default macros
AC_PROG_CC
## Use gsl-config to find arguments for compiler and linker flags
##
## Check for non-standard programs: gsl-config(1)
AC_PATH_PROG([LIB_SBML], [libsbml])
## If gsl-config was found, let's use it
if test "${LIB_SBML}" != ""; then
# Use gsl-config for header and linker arguments
SBML_CFLAGS=`${LIB_SBML} --cflags`
SBML_LIBS=`${LIB_SBML} --libs`
else
AC_MSG_ERROR([libsbml not found, is SBML installed?])
fi
# Now substitute these variables in src/Makevars.in to create src/Makevars
AC_SUBST(LIB_SBML)
AC_SUBST(LIB_SBML)
AC_OUTPUT(src/Makevars)
输出：
string.split("\\+|(?=-)|([=-]?=-)|=");
我的预期输出：
2x^2+3x-9=-2