bp3d_util/

env.rs

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//! This module contains tools to simplify parsing environment variables.

use std::ffi::{OsStr, OsString};

/// Gets the content of an environment variable.
///
/// Returns None if the variable does not exist.
pub fn get_os<T: AsRef<OsStr>>(name: T) -> Option<OsString> {
    std::env::var_os(name)
}

/// Gets the content of an environment variable.
///
/// Returns None if the variable does not exist or is not valid UTF-8.
pub fn get<T: AsRef<OsStr>>(name: T) -> Option<String> {
    get_os(name).and_then(|v| v.into_string().ok())
}

/// Gets a boolean environment variable.
///
/// Returns None if the variable does not exist or the format is unrecognized.
pub fn get_bool<T: AsRef<OsStr>>(name: T) -> Option<bool> {
    match &*get(name)? {
        "off" | "OFF" | "FALSE" | "false" | "0" => Some(false),
        "on" | "ON" | "TRUE" | "true" | "1" => Some(true),
        _ => None,
    }
}