X-Git-Url: https://git.ralfj.de/rust-101.git/blobdiff_plain/63b7a79069a399c32d575bb71832fcad134117c9..e6c369cfcd2d8ae38eb9c5cfbbee685bae2fe64d:/src/part05.rs diff --git a/src/part05.rs b/src/part05.rs index 71d712a..49e57db 100644 --- a/src/part05.rs +++ b/src/part05.rs @@ -47,11 +47,11 @@ impl BigInt { } } - // We can convert any vector of digits into a number, by removing trailing zeros. The `mut` - // declaration for `v` here is just like the one in `let mut ...`: We completely own `v`, but Rust - // still asks us to make our intention of modifying it explicit. This `mut` is *not* part of the - // type of `from_vec` - the caller has to give up ownership of `v` anyway, so they don't care anymore - // what you do to it. + // We can convert any little-endian vector of digits (i.e., least-significant digit first) into a number, + // by removing trailing zeros. The `mut` declaration for `v` here is just like the one in `let mut ...`: + // We completely own `v`, but Rust still asks us to make our intention of modifying it explicit. This + // `mut` is *not* part of the type of `from_vec` - the caller has to give up ownership of `v` anyway, so + // they don't care anymore what you do to it. // // **Exercise 05.1**: Implement this function. // @@ -124,7 +124,7 @@ enum Variant { Text(String), } //@ Now consider the following piece of code. Like above, `n` will be a reference to a part of `var`, -//@ and since we wrote `ref mut`, the reference will be exclusive and mutable. In other words, right after the match, `ptr` +//@ and since we wrote `ref mut`, the reference will be unique and mutable. In other words, right after the match, `ptr` //@ points to the number that's stored in `var`, where `var` is a `Number`. Remember that `_` means //@ "we don't care". fn work_on_variant(mut var: Variant, text: String) { @@ -147,4 +147,4 @@ fn work_on_variant(mut var: Variant, text: String) { //@ I hope this example clarifies why Rust has to rule out mutation in the presence of aliasing *in general*, //@ not just for the specific case of a buffer being reallocated, and old pointers becoming hence invalid. -//@ [index](main.html) | [previous](part04.html) | [raw source](https://www.ralfj.de/git/rust-101.git/blob_plain/HEAD:/workspace/src/part05.rs) | [next](part06.html) +//@ [index](main.html) | [previous](part04.html) | [raw source](workspace/src/part05.rs) | [next](part06.html)