Function env_or

pub fn env_or<'a, T>(name: &'a str, default: T) -> EnvVarDefault<'a, T>

To config some logger setting with env.

Read value from environment, and set with default if not exists.

NOTE: the arguments to load from env_or() must support owned values.

Example:

use captains_log::*;
let _level: log::Level = env_or("LOG_LEVEL", Level::Info).into();
let _file_path: String = env_or("LOG_FILE", "/tmp/test.log").into();
let _console: ConsoleTarget = env_or("LOG_CONSOLE", ConsoleTarget::Stdout).into();