s@source_dir[ 	]*(\([^()]*\))@&\
#undef SOURCE_DIR\
#define SOURCE_DIR \1\
#include "\1/m3makefile"\
#undef SOURCE_DIR\
#define SOURCE_DIR FROM_DIR@g

s@package[ 	]*(\([^()]*\))@&\
#undef SOURCE_DIR\
#define SOURCE_DIR .pkgs/\1\
#include "\1/m3makefile"\
#undef SOURCE_DIR\
#define SOURCE_DIR FROM_DIR@g