Trait ValueSource 

pub trait ValueSource: Send + Sync {
    // Required method
    fn env(&self, name: &str) -> Option<String>;

    // Provided methods
    fn command(&self, _command: &str, _cached: bool) -> Option<String> { ... }
    fn now_unix_seconds(&self) -> i64 { ... }
}

Hosts choose which environment values and commands the runtime may access. Commands are disabled by default; the library never reads process env itself.

Required Methods

fn env(&self, name: &str) -> Option<String>

Provided Methods

fn command(&self, _command: &str, _cached: bool) -> Option<String>

fn now_unix_seconds(&self) -> i64

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl ValueSource for BTreeMap<String, String>

fn env(&self, name: &str) -> Option<String>

Implementors