add CoerceUnsized to the book

Author: basil-cow

book/src/clauses/well_known_traits.md

@@ -28,26 +28,26 @@ Some common examples of auto traits are `Send` and `Sync`.
 [coinductive_section]: ../engine/logic/coinduction.html#coinduction-and-refinement-strands
 
 # Current state 
-| Type            | Copy | Clone | Sized | Unsize | Drop | FnOnce/FnMut/Fn  | Unpin  | Generator | auto traits |
-| ---             | ---  | ---   | ---   | ---    | ---  | --- | ---    |  ---      |  ---        |
-| tuple types     | ✅    | ✅    | ✅     | ✅     | ⚬    | ⚬  |  ⚬      |  ⚬       |   ✅         |
-| structs         | ⚬    | ⚬    |  ✅    | ✅     | ⚬    | ⚬  |  ⚬      |  ⚬       |   ✅         |
-| scalar types    | 📚    | 📚    | ✅     | ⚬     | ⚬   |  ⚬  |  ⚬     |  ⚬       |     ✅       |
-| str             | 📚    | 📚    | ⚬     | ⚬     | ⚬   |  ⚬  |  ⚬     |  ⚬       |     ✅       |
-| never type      | 📚   |  📚   |  ✅   |  ⚬    |  ⚬    | ⚬   |   ⚬    |  ⚬       |  ✅       |
-| trait objects   | ⚬    | ⚬    | ⚬     |  ✅    | ⚬    | ⚬   | ⚬      |  ⚬       |    ⚬        |
-| functions defs  | ✅    | ✅    | ✅     | ⚬     | ⚬    |  ❌  | ⚬      |  ⚬       |     ✅        |
-| functions ptrs  | ✅    | ✅    | ✅     | ⚬     | ⚬    |  ✅  | ⚬      |  ⚬       |     ✅        |
-| raw ptrs        | 📚   |  📚  |   ✅   |  ⚬    |   ⚬   |  ⚬  |   ⚬    |   ⚬      |       ✅     |
-| immutable refs  | 📚   |  📚  |   ✅   |  ⚬    |   ⚬   |  ⚬  |   ⚬    |   ⚬      |       ✅     |
-| mutable refs    | ⚬    |  ⚬   |   ✅   |  ⚬    |   ⚬   |  ⚬  |   ⚬    |   ⚬      |       ✅     |
-| slices          | ⚬     | ⚬    | ⚬     |   ✅    | ⚬   | ⚬   | ⚬      |  ⚬       |     ✅      |
-| arrays          | ✅     | ✅    | ✅     |   ❌    | ⚬   | ⚬   | ⚬      |  ⚬       |     ✅       |
-| closures❌       | ❌     | ❌    | ❌     | ⚬      | ⚬   | ❌   | ⚬      |  ⚬       |     ✅       |
-| generators❌     |  ⚬    |  ⚬  | ❌     |  ⚬     | ⚬    | ⚬  | ❌      |   ❌       |    ❌       |
-| gen. witness❌   |  ⚬    |   ⚬  |  ⚬   |   ⚬    |  ⚬   |  ⚬ |  ⚬    |   ⚬       |    ❌       |
-| -----------     |       |      |       |        |      |     |        |           |             |
-| well-formedness |  ✅   |  ⚬   | ✅     | ⚬     | ✅    |  ⚬  | ⚬      |  ⚬       |   ⚬         |
+| Type            | Copy | Clone | Sized | Unsize | CoerceUnsized | Drop | FnOnce/FnMut/Fn  | Unpin  | Generator | auto traits |
+| ---             | ---  | ---   | ---   | ---   |      ---       | ---  | --- | ---    |  ---      |  ---        |
+| tuple types     | ✅    | ✅    | ✅     | ✅     |  ⚬             | ⚬    | ⚬  |  ⚬      |  ⚬       |   ✅         |
+| structs         | ⚬    | ⚬    |  ✅    | ✅     |  ⚬             | ⚬    | ⚬  |  ⚬      |  ⚬       |   ✅         |
+| scalar types    | 📚    | 📚    | ✅     | ⚬     | ⚬             | ⚬   |  ⚬  |  ⚬     |  ⚬       |    ✅        |
+| str             | 📚    | 📚    | ⚬     | ⚬     | ⚬            | ⚬    |  ⚬  |  ⚬     |  ⚬       |    ✅        |
+| never type      | 📚   |  📚   |  ✅   |  ⚬    |  ⚬            | ⚬     | ⚬   |   ⚬    |  ⚬       |   ✅       |
+| trait objects   | ⚬    | ⚬    | ⚬     |  ✅    | ⚬            | ⚬     | ⚬   | ⚬      |  ⚬       |    ⚬        |
+| functions defs  | ✅    | ✅    | ✅     | ⚬     | ⚬            | ⚬     |  ❌  | ⚬      |  ⚬       |    ✅         |
+| functions ptrs  | ✅    | ✅    | ✅     | ⚬     | ⚬            | ⚬     |  ✅  | ⚬      |  ⚬       |    ✅         |
+| raw ptrs        | 📚   |  📚  |   ✅   |  ⚬    |   ⚬            | ⚬    |  ⚬  |   ⚬    |   ⚬      |      ✅      |
+| immutable refs  | 📚   |  📚  |   ✅   |  ⚬    |   ⚬            | ⚬    |  ⚬  |   ⚬    |   ⚬      |      ✅      |
+| mutable refs    | ⚬    |  ⚬   |   ✅   |  ⚬    |   ⚬            | ⚬    |  ⚬  |   ⚬    |   ⚬      |      ✅      |
+| slices          | ⚬     | ⚬    | ⚬     |   ✅    | ⚬            | ⚬    | ⚬   | ⚬      |  ⚬       |    ✅       |
+| arrays          | ✅     | ✅    | ✅     |   ❌    | ⚬            | ⚬    | ⚬   | ⚬      |  ⚬       |    ✅        |
+| closures❌       | ❌     | ❌    | ❌     | ⚬      | ⚬            | ⚬    | ❌   | ⚬      |  ⚬       |    ✅        |
+| generators❌     |  ⚬    |  ⚬  | ❌     |  ⚬     | ⚬            | ⚬     | ⚬  | ❌      |   ❌       |    ❌       |
+| gen. witness❌   |  ⚬    |   ⚬  |  ⚬   |   ⚬    |  ⚬            | ⚬    |  ⚬ |  ⚬    |   ⚬       |    ❌       |
+| -----------     |       |      |       |        |             |       |     |        |           |             |
+| well-formedness |  ✅   |  ⚬   | ✅     | ⚬     | ✅            | ✅     |  ⚬  | ⚬      |  ⚬       |   ⚬         |
 
 legend:  
 ⚬ - not applicable