Crate expandenv 

This crate is for expanding environment variables in strings with support for fallback values.

Examples

// when you expand a variable, it returns the value
let envvar_value = expand("$FOO")?;

// if expansion fails, you can return an error...
assert!(expand("$MISSING_VAR").is_err());
// or try to parse a fallback value
let envvar_value = expand("${MISSING_VAR:-some/path}")?;
// and nest them as much as you want! this example returns the value of `$FOO`
let envvar_value = expand("${MISSING_VAR:-${ANOTHER_MISSING_VAR:-$FOO}}")?;

// here's where it shines: you can expand an entire string!
let expanded_str = expand("holy mackerel there's a ${MISSING_VAR:-$FOO} and even a $BAR!!")?;

Modules

errors

Custom error type(s).

Functions

expand

Parse through a byte slice, expanding envvars along the way.