# morphix
[](https://crates.io/crates/morphix)
[](https://docs.rs/morphix)
A Rust library for observing and serializing mutations.
## Installation
Add this to your `Cargo.toml`:
```toml
[dependencies]
morphix = { version = "0.3", features = ["json"] }
```
## Basic Usage
```rust
use serde::Serialize;
use serde_json::json;
use morphix::{JsonAdapter, Mutation, MutationKind, Observe, observe};
// 1. Define any data structure with `#[derive(Observe)]`.
#[derive(Serialize, PartialEq, Debug, Observe)]
struct Foo {
pub bar: Bar,
pub qux: String,
}
#[derive(Serialize, PartialEq, Debug, Observe)]
struct Bar {
pub baz: i32,
}
let mut foo = Foo {
bar: Bar { baz: 42 },
qux: "hello".to_string(),
};
// 2. Use `observe!` to mutate data and track mutations.
foo.qux.push(' ');
foo.qux += "world";
}).unwrap();
// 3. Inspect the mutations.
assert_eq!(
mutation,
Some(Mutation {
path: vec![].into(),
kind: MutationKind::Batch(vec![
Mutation {
path: vec!["bar".into(), "baz".into()].into(),
kind: MutationKind::Replace(json!(43)),
},
Mutation {
path: vec!["qux".into()].into(),
kind: MutationKind::Append(json!(" world")),
},
]),
}),
);
// 4. The original data structure is also mutated.
assert_eq!(
foo,
Foo {
bar: Bar { baz: 43 },
qux: "hello world".to_string(),
},
);
```
## Mutation Types
Morphix recognizes three types of mutations:
### Replace
The most general mutation type, used for any mutation that replaces a value:
```rs
foo.a.b = 1; // Replace at .a.b
foo.num *= 2; // Replace at .num
foo.vec.clear(); // Replace at .vec
```
### Append
Optimized for appending to strings and vectors:
```rs
foo.a.b += "text"; // Append to .a.b
foo.a.b.push_str("text"); // Append to .a.b
foo.vec.push(1); // Append to .vec
foo.vec.extend(iter); // Append to .vec
```
### Batch
Multiple mutations combined into a single operation.
## Features
- `derive` (default): Enables the Observe derive macro
- `json`: Includes JSON serialization support via `serde_json`
- `yaml`: Includes YAML serialization support via `serde_yaml_ng`