Struct Config 

pub struct Config { /* private fields */ }

High-level configuration manager with format preservation and change tracking

Config provides a comprehensive API for managing configurations throughout their lifecycle. It maintains both the resolved values (for fast access) and format-specific preservation data (for round-trip editing).

Key Features

• Format Preservation: Maintains comments, whitespace, and original formatting
• Change Tracking: Automatic detection of modifications
• Type Safety: Rich type conversion with comprehensive error handling
• Path-based Access: Dot notation for nested value access
• Multi-format Support: CONF, TOML, JSON, NOML formats
• Schema Validation: Optional schema validation and enforcement
• Async Support: Non-blocking file operations (with feature flag)

Examples

use config_lib::Config;

// Load from string
let mut config = Config::from_string("port = 8080\nname = \"MyApp\"", None)?;

// Access values
let port = config.get("port").unwrap().as_integer()?;
let name = config.get("name").unwrap().as_string()?;

// Modify values
config.set("port", 9000)?;

Implementations

impl Config

pub fn new() -> Self

Create a new empty configuration

pub fn from_string(source: &str, format: Option<&str>) -> Result<Self>

Load configuration from a string

pub fn from_file<P: AsRef<Path>>(path: P) -> Result<Self>

Load configuration from a file

pub fn get(&self, path: &str) -> Option<&Value>

Get a value by path

pub fn get_mut(&mut self, path: &str) -> Result<&mut Value>

Get a mutable reference to a value by path

pub fn set<V: Into<Value>>(&mut self, path: &str, value: V) -> Result<()>

Set a value by path

Errors

Returns an error if:

• The configuration was constructed with ConfigOptions::read_only
• The path is invalid (e.g. attempts to insert into a non-table value)

pub fn remove(&mut self, path: &str) -> Result<Option<Value>>

Remove a value by path

Errors

Returns an error if:

• The configuration was constructed with ConfigOptions::read_only
• The path is malformed

pub fn contains_key(&self, path: &str) -> bool

Check if a path exists

pub fn keys(&self) -> Result<Vec<&str>>

Get all keys in the configuration

pub fn is_modified(&self) -> bool

Check if the configuration has been modified

pub fn mark_clean(&mut self)

Mark the configuration as unmodified

pub fn format(&self) -> &str

Get the configuration format

pub fn file_path(&self) -> Option<&Path>

Get the file path (if loaded from file)

pub fn save(&mut self) -> Result<()>

Save the configuration to its original file

pub fn save_to_file<P: AsRef<Path>>(&self, path: P) -> Result<()>

Save the configuration to a specific file

pub fn serialize(&self) -> Result<String>

Serialize the configuration to string format

pub fn as_value(&self) -> &Value

Get the underlying Value

pub fn merge(&mut self, other: &Config) -> Result<()>

Merge another configuration into this one

Errors

Returns an error if the configuration was constructed with ConfigOptions::read_only.

pub fn key(&self, path: &str) -> ConfigValue<'_>

Get a value by path with a more ergonomic API

pub fn has(&self, path: &str) -> bool

Check if configuration has any value at the given path

pub fn get_or<V>(&self, path: &str, default: V) -> V

where V: TryFrom<Value> + Clone, V::Error: Debug,

Get a value with a default fallback

impl Config

pub fn with_options(options: ConfigOptions) -> Self

Construct a new empty Config with the supplied ConfigOptions.

This is the explicit opt-out constructor. For the canonical defaults (caching on, writes allowed), prefer Config::new.

pub fn options(&self) -> &ConfigOptions

Return the ConfigOptions currently in effect on this config.

pub fn is_read_only(&self) -> bool

Returns true if this configuration was constructed read-only (see ConfigOptions::read_only).

Trait Implementations

impl Default for Config

fn default() -> Self

Returns the “default value” for a type.

impl From<Value> for Config

Convert Value to Config

fn from(value: Value) -> Self

Converts to this type from the input type.