envcast_derive 1.0.0

Short, clear description of what the project does
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# envcast_derive

[![Crates.io](https://img.shields.io/crates/v/envcast_derive.svg)](https://crates.io/crates/envcast_derive)
[![msrv 1.70.0](https://img.shields.io/badge/msrv-1.70.0-dea584.svg?logo=rust)](https://github.com/rust-lang/rust/releases/tag/1.70.0)
[![ci](https://github.com/neamaddin/envcast/actions/workflows/ci.yml/badge.svg)](https://github.com/neamaddin/envcast/actions/workflows/ci.yml)
[![docs](https://img.shields.io/docsrs/envcast_derive?logo=docs.rs)](https://docs.rs/envcast_derive/)

## Overview

`envcast_derive` provides the `FromEnv` procedural macro for Rust structs.
It generates a `get()` method that resolves struct fields using the following order:

1. Environment variables (field name as-is, then uppercase)
2. `.env` files (default `.env`, then `DOTENV_CONFIG_FILE`), lowercase and uppercase keys
3. `#[default = "..."]` attribute
4. `Default::default()`

Each field type must implement:

- `std::str::FromStr`
- `Default`

## Usage

```rust
use envcast::FromEnv;

#[derive(FromEnv)]
pub struct Config {
    #[default = 50]
    pub int_field: i32,

    #[default = 50.0]
    pub float_field: f32,

    #[default = "Rust"]
    pub string_field: String,

    #[default = true]
    pub bool_field: bool,
}
```

Then:

```rust
let cfg = Config::get();
```

`Config::get()` returns a struct with all fields resolved according to the priority rules above.

## License

MIT