lifetime problems

red_black_tree.rs:100:8: 100:12 error: illegal borrow: cannot root managed value long enough
red_black_tree.rs:100         left.each(f);
                              ^~~~
red_black_tree.rs:96:58: 108:3 note: managed value would have to be rooted for the lifetime &self as defined on the block at 96:58...
red_black_tree.rs:96   pure fn each(&self, f: fn(&(&self/K, &self/V)) -> bool) {
red_black_tree.rs:97     match *self {
red_black_tree.rs:98       Leaf => (),
red_black_tree.rs:99       Tree(_, left, key, maybe_value, right) => {
red_black_tree.rs:100         left.each(f);
red_black_tree.rs:101         match maybe_value {
                      ...
red_black_tree.rs:96:58: 108:3 note: ...but can only be rooted for the block at 96:58
red_black_tree.rs:96   pure fn each(&self, f: fn(&(&self/K, &self/V)) -> bool) {
red_black_tree.rs:97     match *self {
red_black_tree.rs:98       Leaf => (),
red_black_tree.rs:99       Tree(_, left, key, maybe_value, right) => {
red_black_tree.rs:100         left.each(f);
red_black_tree.rs:101         match maybe_value {
                      ...
red_black_tree.rs:102:30: 102:33 error: illegal borrow: borrowed value does not live long enough
red_black_tree.rs:102           Some(value) => f(&(&key, &value)),
                                                    ^~~
red_black_tree.rs:96:58: 108:3 note: borrowed pointer must be valid for the lifetime &self as defined on the block at 96:58...
red_black_tree.rs:96   pure fn each(&self, f: fn(&(&self/K, &self/V)) -> bool) {
red_black_tree.rs:97     match *self {
red_black_tree.rs:98       Leaf => (),
red_black_tree.rs:99       Tree(_, left, key, maybe_value, right) => {
red_black_tree.rs:100         left.each(f);
red_black_tree.rs:101         match maybe_value {
                      ...
red_black_tree.rs:97:4: 107:5 note: ...but borrowed value is only valid for the match at 97:4
red_black_tree.rs:97     match *self {
red_black_tree.rs:98       Leaf => (),
red_black_tree.rs:99       Tree(_, left, key, maybe_value, right) => {
red_black_tree.rs:100         left.each(f);
red_black_tree.rs:101         match maybe_value {
red_black_tree.rs:102           Some(value) => f(&(&key, &value)),
                      ...
red_black_tree.rs:102:36: 102:41 error: illegal borrow: borrowed value does not live long enough
red_black_tree.rs:102           Some(value) => f(&(&key, &value)),
                                                          ^~~~~
red_black_tree.rs:96:58: 108:3 note: borrowed pointer must be valid for the lifetime &self as defined on the block at 96:58...
red_black_tree.rs:96   pure fn each(&self, f: fn(&(&self/K, &self/V)) -> bool) {
red_black_tree.rs:97     match *self {
red_black_tree.rs:98       Leaf => (),
red_black_tree.rs:99       Tree(_, left, key, maybe_value, right) => {
red_black_tree.rs:100         left.each(f);
red_black_tree.rs:101         match maybe_value {
                      ...
red_black_tree.rs:101:8: 104:9 note: ...but borrowed value is only valid for the match at 101:8
red_black_tree.rs:101         match maybe_value {
red_black_tree.rs:102           Some(value) => f(&(&key, &value)),
red_black_tree.rs:103           None => false,
red_black_tree.rs:104         };
red_black_tree.rs:105:8: 105:13 error: illegal borrow: cannot root managed value long enough
red_black_tree.rs:105         right.each(f);
                              ^~~~~
red_black_tree.rs:96:58: 108:3 note: managed value would have to be rooted for the lifetime &self as defined on the block at 96:58...
red_black_tree.rs:96   pure fn each(&self, f: fn(&(&self/K, &self/V)) -> bool) {
red_black_tree.rs:97     match *self {
red_black_tree.rs:98       Leaf => (),
red_black_tree.rs:99       Tree(_, left, key, maybe_value, right) => {
red_black_tree.rs:100         left.each(f);
red_black_tree.rs:101         match maybe_value {
                      ...
red_black_tree.rs:96:58: 108:3 note: ...but can only be rooted for the block at 96:58
red_black_tree.rs:96   pure fn each(&self, f: fn(&(&self/K, &self/V)) -> bool) {
red_black_tree.rs:97     match *self {
red_black_tree.rs:98       Leaf => (),
red_black_tree.rs:99       Tree(_, left, key, maybe_value, right) => {
red_black_tree.rs:100         left.each(f);
red_black_tree.rs:101         match maybe_value {
                      ...
error: aborting due to 4 previous errors
make: *** [all] Error 101