77 lines
1.0 KiB
Markdown
77 lines
1.0 KiB
Markdown
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# Tree hashing
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Provides both cached and non-cached tree hashing methods.
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## Standard Tree Hash
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```rust
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use tree_hash_derive::TreeHash;
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#[derive(TreeHash)]
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struct Foo {
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a: u64,
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b: Vec<u64>,
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}
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fn main() {
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let foo = Foo {
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a: 42,
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b: vec![1, 2, 3]
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};
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println!("root: {}", foo.tree_hash_root());
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}
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```
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## Cached Tree Hash
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```rust
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use tree_hash_derive::{TreeHash, CachedTreeHash};
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#[derive(TreeHash, CachedTreeHash)]
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struct Foo {
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a: u64,
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b: Vec<u64>,
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}
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#[derive(TreeHash, CachedTreeHash)]
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struct Bar {
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a: Vec<Foo>,
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b: u64,
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}
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fn main() {
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let bar = Bar {
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a: vec![
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Foo {
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a: 42,
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b: vec![1, 2, 3]
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}
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],
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b: 42
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};
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let modified_bar = Bar {
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a: vec![
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Foo {
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a: 100,
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b: vec![1, 2, 3, 4, 5, 6]
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},
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Foo {
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a: 42,
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b: vec![]
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}
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],
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b: 99
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};
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let mut hasher = CachedTreeHasher::new(&bar).unwrap();
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hasher.update(&modified_bar).unwrap();
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// Assert that the cached tree hash matches a standard tree hash.
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assert_eq!(hasher.tree_hash_root(), modified_bar.tree_hash_root());
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}
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```
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