diff options
Diffstat (limited to 'src/doc/book/listings/ch19-advanced-features/listing-19-05')
4 files changed, 43 insertions, 0 deletions
diff --git a/src/doc/book/listings/ch19-advanced-features/listing-19-05/Cargo.lock b/src/doc/book/listings/ch19-advanced-features/listing-19-05/Cargo.lock new file mode 100644 index 000000000..497817bf2 --- /dev/null +++ b/src/doc/book/listings/ch19-advanced-features/listing-19-05/Cargo.lock @@ -0,0 +1,6 @@ +# This file is automatically @generated by Cargo. +# It is not intended for manual editing. +[[package]] +name = "unsafe-example" +version = "0.1.0" + diff --git a/src/doc/book/listings/ch19-advanced-features/listing-19-05/Cargo.toml b/src/doc/book/listings/ch19-advanced-features/listing-19-05/Cargo.toml new file mode 100644 index 000000000..3e8a29201 --- /dev/null +++ b/src/doc/book/listings/ch19-advanced-features/listing-19-05/Cargo.toml @@ -0,0 +1,6 @@ +[package] +name = "unsafe-example" +version = "0.1.0" +edition = "2021" + +[dependencies] diff --git a/src/doc/book/listings/ch19-advanced-features/listing-19-05/output.txt b/src/doc/book/listings/ch19-advanced-features/listing-19-05/output.txt new file mode 100644 index 000000000..f4b7582ac --- /dev/null +++ b/src/doc/book/listings/ch19-advanced-features/listing-19-05/output.txt @@ -0,0 +1,17 @@ +$ cargo run + Compiling unsafe-example v0.1.0 (file:///projects/unsafe-example) +error[E0499]: cannot borrow `*values` as mutable more than once at a time + --> src/main.rs:6:31 + | +1 | fn split_at_mut(values: &mut [i32], mid: usize) -> (&mut [i32], &mut [i32]) { + | - let's call the lifetime of this reference `'1` +... +6 | (&mut values[..mid], &mut values[mid..]) + | --------------------------^^^^^^-------- + | | | | + | | | second mutable borrow occurs here + | | first mutable borrow occurs here + | returning this value requires that `*values` is borrowed for `'1` + +For more information about this error, try `rustc --explain E0499`. +error: could not compile `unsafe-example` due to previous error diff --git a/src/doc/book/listings/ch19-advanced-features/listing-19-05/src/main.rs b/src/doc/book/listings/ch19-advanced-features/listing-19-05/src/main.rs new file mode 100644 index 000000000..dabf63de1 --- /dev/null +++ b/src/doc/book/listings/ch19-advanced-features/listing-19-05/src/main.rs @@ -0,0 +1,14 @@ +// ANCHOR: here +fn split_at_mut(values: &mut [i32], mid: usize) -> (&mut [i32], &mut [i32]) { + let len = values.len(); + + assert!(mid <= len); + + (&mut values[..mid], &mut values[mid..]) +} +// ANCHOR_END: here + +fn main() { + let mut vector = vec![1, 2, 3, 4, 5, 6]; + let (left, right) = split_at_mut(&mut vector, 3); +} |