Struct EnvLayer 

pub struct EnvLayer { /* private fields */ }

Settings read from environment variables.

Implementations

impl EnvLayer

pub fn from_process() -> Self

The variables this process was started with.

std::env::vars panics on a name or value that is not UTF-8, which would take the CLI down before it resolved anything — over a variable that in all likelihood belongs to something else entirely. Read as OS strings and skipped when they will not convert: a setting whose variable holds bytes this cannot read has no value it could have been given anyway.

pub fn new(vars: impl IntoIterator<Item = (String, String)>) -> Self

A named environment, for a test or for a CLI that has its own idea of one.

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

What this layer would read for name, if anything.

Trait Implementations

impl Layer for EnvLayer

fn source(&self) -> SourceKind

Which kind of place this reads. Used by the scope check and reported by explain.

fn load(&self, ctx: &LayerCtx) -> Result<LayerOutput, LayerError>

Everything this layer has to say, in one pass.