1 AC_DEFUN([st_SAVE_VAR], [dnl 2 AS_IF([test -n "${$1+set}"], [st_saved_$1="${$1}"; unset $1]) 3 ]) 4 5 AC_DEFUN([st_RESTORE_VAR], [dnl 6 AS_IF([test -n "${st_saved_$1+set}"], [$1="${st_saved_$1}"; unset st_saved_$1]) 7 ]) 8