I am trying to build a method on self that builds a set of reverse lookup structures based on the information in a passed in structures. I used methods on the parameter to get iterators to get everything that needs to be looked up. (I did have this as a free standing methods. I thought it would be better as a structure method, and hoped that would fix this problem. But it didn't. The compiler is complaining about moves into the closures:

    pub fn mk_indices(&mut self, rolo: &RolodexBase) {
        self.short_label_list = Vec::new();
        self.long_label_list = Vec::new();
        self.label_to_cat = HashMap::new();

        rolo.short_cat_iter().into_iter().map(|cstr| {
            rolo.cat_label_iter(cstr.clone()).into_iter().map(move |label| {
                self.short_label_list.push(label.clone());
                self.label_to_cat.insert(label.clone(), cstr.clone());
            })
        });
        rolo.long_cat_iter().into_iter().map(|cstr| {
            rolo.cat_label_iter(cstr.clone()).into_iter().map(move |label| {
                self.long_label_list.push(label.clone());
                self.label_to_cat.insert(label.clone(), cstr.clone());
            })
        });
    }

And the compiler errors are:

error[E0507]: cannot move out of `self`, a captured variable in an `FnMut` closure
   --> src\rolo_window\person_gui.rs:81:63
    |
 69 |     pub fn mk_indices(&mut self, rolo: &RolodexBase) {
    |                       ---------
    |                       |
    |                       captured outer variable
    |                       move occurs because `self` has type `&mut PeopleGuiState`, which does not implement the `Copy` trait
...
 80 |         rolo.long_cat_iter().into_iter().map(|cstr| {
    |                                              ------ captured by this `FnMut` closure
 81 |             rolo.cat_label_iter(cstr.clone()).into_iter().map(move |label| {
    |                                                               ^^^^^^^^^^^^ `self` is moved here
 82 |                 self.long_label_list.push(label.clone());
    |                 -------------------- variable moved due to use in closure
    |
help: `Fn` and `FnMut` closures require captured values to be able to be consumed multiple times, but `FnOnce` closures may consume them only once
   --> C:\Users\jmh\.rustup\toolchains\stable-x86_64-pc-windows-msvc\lib/rustlib/src/rust\library\core\src\iter\traits\iterator.rs:776:12
    |
776 |         F: FnMut(Self::Item) -> B,
    |            ^^^^^^^^^^^^^^^^^^^^^^

error[E0382]: use of moved value: `self`
  --> src\rolo_window\person_gui.rs:80:46
   |
69 |     pub fn mk_indices(&mut self, rolo: &RolodexBase) {
   |                       --------- move occurs because `self` has type `&mut PeopleGuiState`, which does not implement the `Copy` trait
...
74 |         rolo.short_cat_iter().into_iter().map(|cstr| {
   |                                               ------ value moved into closure here
75 |             rolo.cat_label_iter(cstr.clone()).into_iter().map(move |label| {
76 |                 self.short_label_list.push(label.clone());
   |                 --------------------- variable moved due to use in closure
...
80 |         rolo.long_cat_iter().into_iter().map(|cstr| {
   |                                              ^^^^^^ value used here after move
81 |             rolo.cat_label_iter(cstr.clone()).into_iter().map(move |label| {
82 |                 self.long_label_list.push(label.clone());
   |                 -------------------- use occurs due to use in closure

The point is to mutate self. Copying it to use in the iterators won't do.
I tried using local variables instead of the self fields, and it gave me similar errors with proposed resolutions that would not leave the constructed information after the iterations.
I presume I ma missing something obvious. But staring at it for a few hours didn't reveal anything. Sorry.
Thanks,
Joel

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