Struct Snapshot 

pub struct Snapshot { /* private fields */ }

A resolved configuration section, before it becomes a struct.

Obtained from snapshot, compared with diff, and turned into a struct with extract.

Implementations

impl Snapshot

pub fn extract<T: DeserializeOwned>(&self) -> Result<T, Error>

Deserializes the section into T.

Errors

If a required value is missing or cannot become the field’s type.

Errors here carry the key path but not the originating file or variable: provenance lives in figment’s metadata, which a snapshot has already left behind. Call load when the error is going to be read by a person.

pub fn diff(&self, other: &Self) -> Vec<Change>

Every key that differs between self and other, in path order.

self is the earlier snapshot, so a key present only in other is Added.

pub fn get<T: DeserializeOwned>(&self, path: &str) -> Result<T, Error>

Reads one value by dotted path, without a struct to hold it.

For the shape a program does not know at compile time: a plugin’s section, a user-defined table. Everything else should go through a struct, where a typo is a compile error rather than a runtime one.

Errors

If nothing supplies path, or the value cannot become T.

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

Whether anything supplies path.

pub fn sub(&self, path: &str) -> Option<Self>

The table at path, as a snapshot of its own.

The analogue of Viper’s Sub: hand a subsystem the part of the configuration it owns and nothing else.

pub fn leaf_paths(&self) -> Vec<String>

The dotted path of every leaf, in order.

pub fn top_level_keys(&self) -> Vec<String>

The section’s immediate keys — the level a struct’s fields map onto.

pub fn is_empty(&self) -> bool

Whether the section resolved to nothing at all.

Trait Implementations

impl Clone for Snapshot

fn clone(&self) -> Snapshot

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Snapshot

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Snapshot

fn default() -> Snapshot

Returns the “default value” for a type.