WR6LRCACDQ7ENL3X5ZJOYNZCN7FYPBELYGBPWWUTQPDYZ7FIBNIQC
#AC_CHECK_LIB([expr], [_ZN3nix17parseExprFromFileERNS_9EvalStateESs], [:],
# [AC_MSG_ERROR([Nix library not found; please install Nix or check the `--with-nix' option.])])
AC_CHECK_LIB([expr], [_ZN3nix17parseExprFromFileERNS_9EvalStateESs], [:],
[AC_MSG_ERROR([Nix library not found; please install Nix or check the `--with-nix' option.])])