Crate nested_env_parser

Nested Env Parser is a crate for getting the final value of a string with nested environment variables.

installation

Install using cargo:

cargo install nested-env-parser

Usage

On Unix

use clap::Parser;
use nested_env_parser::Env;

#[derive(Clone, Debug, Parser)]
struct Opts {
    #[clap(env)]
    value_with_env: Env,
}

fn main() {
    std::env::set_var("VALUE1", "Hello,");
    std::env::set_var("VALUE2", "world");
    std::env::set_var("VALUE_WITH_ENV", "$VALUE1 ${VALUE2}!");

    let opts = Opts::parse();

    assert_eq!("Hello, world!", &opts.value_with_env);
}

On Windows

use clap::Parser;
use nested_env_parser::Env;

#[derive(Clone, Debug, Parser)]
struct Opts {
    #[clap(env)]
    value_with_env: Env,
}

fn main() {
    std::env::set_var("VALUE1", "Hello");
    std::env::set_var("VALUE2", "world");
    std::env::set_var("VALUE_WITH_ENV", "%VALUE1%, %VALUE2%!");

    let opts = Opts::parse();

    assert_eq!("Hello, world!", &opts.value_with_env);
}

Structs

• Env
  String with nested environment variables