[][src]Crate toml_edit

toml_edit

This crate allows you to parse and modify toml documents, while preserving comments, spaces* and relative order* or items.

It is primarily tailored to the needs of cargo-edit.

Example

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:

  • Different quotes and spaces around the same table key, e.g.
[ 'a'. b]
[ "a"  .c]
[a.d]

will be represented as (spaces are removed, the first encountered quote type is used)

['a'.b]
['a'.c]
['a'.d]
  • Children tables before parent table (tables are reordered by default, see test).
  • Scattered array of tables (tables are reordered by default, 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. If you care about the above two cases, you can use Document::to_string_in_original_order() to reconstruct tables in their original order.

Structs

Array

Type representing a TOML array, payload of the Value::Array variant's value

ArrayOfTables

Type representing a TOML array of tables

Document

Type representing a TOML document

InlineTable

Type representing a TOML inline table, payload of the Value::InlineTable variant

Key

Key as part of a Key/Value Pair or a table header.

Table

Type representing a TOML non-inline table

TomlError

Type representing a TOML parse error

Enums

Item

Type representing either a value, a table, an array of tables, or none.

Value

Representation of a TOML Value (as part of a Key/Value Pair).

Traits

TableLike

This trait represents either a Table, or an InlineTable.

Functions

array

Returns an empty array of tables.

decorated

Sets the prefix and the suffix for value.

table

Returns an empty table.

value

Returns a formatted value.

Type Definitions

Iter

An iterator type over Table's key/value pairs.