rules() {
    export LOCAL_BOOTSTRAP="no"
    pushd ${WORK_DIR} 2>&1>/dev/null
    ( xzcat rust.url.patch.xz | patch -p1 ) || return 1
    BOOTSTRAP_DATE=$(grep BOOTSTRAP_DATE= rust.url | cut -d '=' -f2)
    BOOTSTRAP_VERSION=$(grep BOOTSTRAP_VERSION= rust.url | cut -d '=' -f2)
    BOOTSTRAP_CARGO=$(grep BOOTSTRAP_CARGO= rust.url | cut -d '=' -f2)

    [[ $BOOTSTRAP_CARGO == \$* ]] && BOOTSTRAP_CARGO=$(echo $BOOTSTRAP_CARGO | sed 's:\$::g') && BOOTSTRAP_CARGO=${!BOOTSTRAP_CARGO}

    echo
    echo "\$BOOTSTRAP_DATE = $BOOTSTRAP_DATE"
    echo "\$BOOTSTRAP_VERSION = $BOOTSTRAP_VERSION"
    echo "\$BOOTSTRAP_CARGO = $BOOTSTRAP_CARGO"
    echo

    ( grep ${MARCH} rust.url | sed -e "s:\${BOOTSTRAP_DATE}:$BOOTSTRAP_DATE:g" \
        -e "s:\${BOOTSTRAP_VERSION}:$BOOTSTRAP_VERSION:g" \
        -e "s:\${BOOTSTRAP_CARGO}:$BOOTSTRAP_CARGO:g" \
      | sh
    ) || return 1
    popd 2>&1>/dev/null
}

rules