Mercurial > hg
comparison rust/hg-core/examples/nodemap/main.rs @ 50979:4c5f6e95df84
rust: make `Revision` a newtype
This change is the one we've been building towards during this series.
The aim is to make `Revision` mean more than a simple integer, holding
the information that it is valid for a given revlog index.
While this still allows for programmer error, since creating a revision
directly and querying a different index with a "checked" revision are
still possible, the friction created by the newtype will hopefully make
us think twice about which type to use.
Enough of the Rust ecosystem relies on the newtype pattern to be
efficiently optimized away (even compiler in codegen testsĀ¹), so I'm not
worried about this being a fundamental problem.
[1] https://github.com/rust-lang/rust/blob/7a70647f195f6b0a0f1ebd72b1542ba91a32f43a/tests/codegen/vec-in-place.rs#L47
author | Raphaël Gomès <rgomes@octobus.net> |
---|---|
date | Fri, 18 Aug 2023 14:34:29 +0200 |
parents | 0d301f4180f5 |
children |
comparison
equal
deleted
inserted
replaced
50978:27e773aa607d | 50979:4c5f6e95df84 |
---|---|
34 fn create(index: &Index, path: &Path) -> io::Result<()> { | 34 fn create(index: &Index, path: &Path) -> io::Result<()> { |
35 let mut file = File::create(path)?; | 35 let mut file = File::create(path)?; |
36 let start = Instant::now(); | 36 let start = Instant::now(); |
37 let mut nm = NodeTree::default(); | 37 let mut nm = NodeTree::default(); |
38 for rev in 0..index.len() { | 38 for rev in 0..index.len() { |
39 let rev = rev as Revision; | 39 let rev = Revision(rev as BaseRevision); |
40 nm.insert(index, index.node(rev).unwrap(), rev).unwrap(); | 40 nm.insert(index, index.node(rev).unwrap(), rev).unwrap(); |
41 } | 41 } |
42 eprintln!("Nodemap constructed in RAM in {:?}", start.elapsed()); | 42 eprintln!("Nodemap constructed in RAM in {:?}", start.elapsed()); |
43 file.write_all(&nm.into_readonly_and_added_bytes().1)?; | 43 file.write_all(&nm.into_readonly_and_added_bytes().1)?; |
44 eprintln!("Nodemap written to disk"); | 44 eprintln!("Nodemap written to disk"); |
53 | 53 |
54 fn bench(index: &Index, nm: &NodeTree, queries: usize) { | 54 fn bench(index: &Index, nm: &NodeTree, queries: usize) { |
55 let len = index.len() as u32; | 55 let len = index.len() as u32; |
56 let mut rng = rand::thread_rng(); | 56 let mut rng = rand::thread_rng(); |
57 let nodes: Vec<Node> = (0..queries) | 57 let nodes: Vec<Node> = (0..queries) |
58 .map(|_| *index.node((rng.gen::<u32>() % len) as Revision).unwrap()) | 58 .map(|_| { |
59 *index | |
60 .node(Revision((rng.gen::<u32>() % len) as BaseRevision)) | |
61 .unwrap() | |
62 }) | |
59 .collect(); | 63 .collect(); |
60 if queries < 10 { | 64 if queries < 10 { |
61 let nodes_hex: Vec<String> = | 65 let nodes_hex: Vec<String> = |
62 nodes.iter().map(|n| format!("{:x}", n)).collect(); | 66 nodes.iter().map(|n| format!("{:x}", n)).collect(); |
63 println!("Nodes: {:?}", nodes_hex); | 67 println!("Nodes: {:?}", nodes_hex); |