# toml_edit
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This crate allows you to parse and modify toml
documents, while preserving comments, spaces* and
relative order* or items.
`toml_edit` is primarily tailored for [cargo-edit](https://github.com/killercup/cargo-edit/) needs.
## Example
```rust
extern crate toml_edit;
use toml_edit::{Document, value};
fn main() {
let toml = r#"
"hello" = 'toml!' # comment
['a'.b]
"#;
let mut doc = toml.parse::<Document>().expect("invalid doc");
assert_eq!(doc.to_string(), toml);
// let's add a new key/value pair inside a.b: c = {d = "hello"}
doc["a"]["b"]["c"]["d"] = value("hello");
// autoformat inline table a.b.c: { d = "hello" }
doc["a"]["b"]["c"].as_inline_table_mut().map(|t| t.fmt());
let expected = r#"
"hello" = 'toml!' # comment
['a'.b]
c = { d = "hello" }
"#;
assert_eq!(doc.to_string(), expected);
}
```
## Limitations
*Things it does not preserve:
1. Different quotes and spaces around the same table key, e.g.
```toml
[ 'a'. b]
[ "a" .c]
[a.d]
```
will be represented as (spaces are removed, the first encountered quote type is used)
```toml
['a'.b]
['a'.c]
['a'.d]
```
2. Children tables before parent table (tables are reordered, see [test]).
3. Scattered array of tables (tables are reordered, see [test]).
The reason behind the first limitation is that `Table` does not store its header,
allowing us to safely swap two tables (we store a mapping in each table: child key -> child table).
This last two limitations allow us to represent a toml document as a tree-like data structure,
which enables easier implementation of editing operations
and an easy to use and type-safe API.
## License
Licensed under either of
- Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or http://apache.org/licenses/LICENSE-2.0)
- MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
### Contribution
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.
[test]: https://github.com/ordian/toml_edit/blob/f09bd5d075fdb7d2ef8d9bb3270a34506c276753/tests/test_valid.rs#L84