Trait Env 

pub trait Env {
    // Required method
    fn lookup(&self, name: &str) -> Option<EnvValue>;
}

Where ${env:NAME} reads from.

A trait rather than a direct std::env::var call so that resolution never touches process state; ProcessEnv is the one implementation that does.

Required Methods

fn lookup(&self, name: &str) -> Option<EnvValue>

The variable, or None if it is unset.

Dyn Compatibility

This trait is dyn compatible.

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

Implementors

impl Env for ProcessEnv