itconfig 1.1.1

Easy build a configs from environment variables and use it in globally.
Documentation
//! # itconfig
//!
//! Simple configuration with macro for rust application.
//!
//!
//! ## Motivation
//!
//! I began to use rust with web programming experience where environment variables are widely used
//! and often there are more then 50 of them. First I looked at already created libraries.
//! But there it's necessary to initialise structure that needs to be moved to each function
//! where you need variable. It uses little bit memory, but configuration lifetime is as long
//! as application lifetime. Because of it I decided to create my own library.
//!
//!
//! ## Installation
//!
//! These macros require a Rust compiler version 1.31 or newer.
//!
//! Add `itconfig = { version = "1.0", features = ["macro"] }` as a dependency in `Cargo.toml`.
//!
//!
//! `Cargo.toml` example:
//!
//! ```toml
//! [package]
//! name = "my-crate"
//! version = "0.1.0"
//! authors = ["Me <user@rust-lang.org>"]
//!
//! [dependencies]
//! itconfig = { version = "1.0", features = ["macro"] }
//! ```
//!
//!
//! ## Basic usage
//!
//! ```rust
//! use itconfig::config;
//! use std::env;
//! //use dotenv::dotenv;
//!
//! config! {
//!     DEBUG: bool => false,
//!
//!     #[env_name = "APP_HOST"]
//!     HOST: String => "127.0.0.1",
//!
//!     database {
//!         URL < (
//!             "postgres://",
//!             POSTGRES_USERNAME => "user",
//!             ":",
//!             POSTGRES_PASSWORD => "pass",
//!             "@",
//!             POSTGRES_HOST => "localhost:5432",
//!             "/",
//!             POSTGRES_DB => "test",
//!         ),
//!
//!         pool {
//!             MAX_SIZE: usize => 15,
//!         },
//!     },
//!
//!     sentry {
//!         DSN: Option<&'static str>,
//!     },
//!
//!     feature {
//!         static CORS: bool => false,
//!
//!         static GRAPHQL_PLAYGROUND: bool => false,
//!     },
//! }
//!
//! fn main () {
//!     // dotenv().expect("dotenv setup to be successful");
//!     // or
//!     env::set_var("FEATURE_CORS", "true");
//!
//!     config::init();
//!     assert_eq!(config::HOST(), String::from("127.0.0.1"));
//!     assert_eq!(config::database::URL(), String::from("postgres://user:pass@localhost:5432/test"));
//!     assert_eq!(config::database::pool::MAX_SIZE(), 15);
//!     assert_eq!(config::sentry::DSN(), None);
//!     assert_eq!(config::feature::CORS(), true);
//! }
//! ```
//!
//! Macro is an optional feature, disabled by default. You can use this library without macro.
//!
//! ```rust
//! use itconfig::*;
//! use std::env;
//! // use dotenv::dotenv;
//!
//! fn main() {
//!     // dotenv().expect("dotenv setup to be successful");
//!     // or
//!     env::set_var("DATABASE_URL", "postgres://127.0.0.1:5432/test");
//!
//!     let database_url = get_env::<String>("DATABASE_URL").unwrap();
//!     let new_profile: bool = get_env_or_default("FEATURE_NEW_PROFILE", false);
//!     let articles_per_page: u32 = get_env_or_set_default("ARTICLES_PER_PAGE", 10);
//! }
//! ```
//!
//! ## Available features
//!
//! * **default** - ["primitives"]
//! * **macro** - Activates `config!` macros for easy configure web application.
//! * **primitives** - Group for features: `numbers` and `bool`.
//! * **numbers** - Group for features: `int`, `uint` and `float`.
//! * **int** - Group for features: `i8`, `i16`, `i32`, `i64`, `i128` and `isize`.
//! * **uint** - Group for features: `u8`, `u16`, `u32`, `u64`, `u128` and `usize`.
//! * **float** - Group for features: `f32` and `f64`
//! * **i8** - impl EnvString for `i8` type
//! * **i16** - impl EnvString for `i16` type
//! * **i32** - impl EnvString for `i32` type
//! * **i64** - impl EnvString for `i64` type
//! * **i128** - impl EnvString for `i128` type
//! * **isize** - impl EnvString for `isize` type
//! * **u8** - impl EnvString for `u8` type
//! * **u16** - impl EnvString for `u16` type
//! * **u32** - impl EnvString for `u32` type
//! * **u64** - impl EnvString for `u64` type
//! * **u128** - impl EnvString for `u128` type
//! * **usize** - impl EnvString for `usize` type
//! * **f32** - impl EnvString for `f32` type
//! * **f64** - impl EnvString for `f64` type
//! * **bool** - impl EnvString for `bool` type
//! * **json_array** - Add EnvString impl for vector type (uses optional `serde_json` package). ⚠ **_DEPRECATED_**
//!

// Rustc lints.
#![forbid(unsafe_code)]
#![forbid(non_ascii_idents)]
#![deny(
    missing_debug_implementations,
    missing_docs,
    unstable_features,
    unused_imports,
    unused_qualifications
)]
// Clippy lints
#![deny(clippy::all)]
#![allow(clippy::needless_doctest_main)]

/////////////////////////////////////////////////////////////////////////////

mod envstr;
mod error;
mod get_env;
mod get_vec_env;
pub(crate) mod utils;

pub use self::envstr::*;
pub use self::error::*;
pub use self::get_env::*;
pub use self::get_vec_env::*;

#[cfg(feature = "macro")]
extern crate itconfig_macro;
#[cfg(feature = "macro")]
pub use itconfig_macro::*;