Clean up E0374 explanation

This commit is contained in:
Guillaume Gomez 2020-02-28 16:06:30 +01:00
parent abc3073c92
commit 45053d1fa6

View File

@ -1,9 +1,5 @@
A struct without a field containing an unsized type cannot implement
`CoerceUnsized`. An [unsized type][1] is any type that the compiler
doesn't know the length or alignment of at compile time. Any struct
containing an unsized type is also unsized.
[1]: https://doc.rust-lang.org/book/ch19-04-advanced-types.html#dynamically-sized-types-and-the-sized-trait
`CoerceUnsized` was implemented on a struct which does not contain a field with
an unsized type.
Example of erroneous code:
@ -20,6 +16,12 @@ impl<T, U> CoerceUnsized<Foo<U>> for Foo<T>
where T: CoerceUnsized<U> {}
```
An [unsized type][1] is any type where the compiler does not know the length or
alignment of at compile time. Any struct containing an unsized type is also
unsized.
[1]: https://doc.rust-lang.org/book/ch19-04-advanced-types.html#dynamically-sized-types-and-the-sized-trait
`CoerceUnsized` is used to coerce one struct containing an unsized type
into another struct containing a different unsized type. If the struct
doesn't have any fields of unsized types then you don't need explicit