[rustc.git] / src / librustc_error_codes / error_codes / E0605.md

An invalid cast was attempted.

Erroneous code examples:

```compile_fail,E0605
let x = 0u8;
x as Vec<u8>; // error: non-primitive cast: `u8` as `std::vec::Vec<u8>`

// Another example

let v = core::ptr::null::<u8>(); // So here, `v` is a `*const u8`.
v as &u8; // error: non-primitive cast: `*const u8` as `&u8`
```

Only primitive types can be cast into each other. Examples:

```
let x = 0u8;
x as u32; // ok!

let v = core::ptr::null::<u8>();
v as *const i8; // ok!
```

For more information about casts, take a look at the Type cast section in
[The Reference Book][1].

[1]: https://doc.rust-lang.org/reference/expressions/operator-expr.html#type-cast-expressions
Commit	Line	Data
60c5eb7d XL	1	An invalid cast was attempted.
	2
	3	Erroneous code examples:
	4
	5	```compile_fail,E0605
	6	let x = 0u8;
	7	x as Vec<u8>; // error: non-primitive cast: `u8` as `std::vec::Vec<u8>`
	8
	9	// Another example
	10
	11	let v = core::ptr::null::<u8>(); // So here, `v` is a `*const u8`.
	12	v as &u8; // error: non-primitive cast: `*const u8` as `&u8`
	13	```
	14
	15	Only primitive types can be cast into each other. Examples:
	16
	17	```
	18	let x = 0u8;
	19	x as u32; // ok!
	20
	21	let v = core::ptr::null::<u8>();
	22	v as *const i8; // ok!
	23	```
	24
	25	For more information about casts, take a look at the Type cast section in
	26	[The Reference Book][1].
	27
	28	[1]: https://doc.rust-lang.org/reference/expressions/operator-expr.html#type-cast-expressions