serde-inline-default 1.0.1

Serde default values via inline declaration
Documentation 
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# serde-inline-default [![ci](https://github.com/ByteDream/serde-inline-default/actions/workflows/ci.yml/badge.svg)](https://github.com/ByteDream/serde-inline-default/actions/workflows/ci.yml) [![crates.io](https://img.shields.io/crates/v/serde-inline-default)](https://crates.io/crates/serde-inline-default) [![crates.io downloads](https://img.shields.io/crates/d/serde-inline-default)](https://crates.io/crates/serde-inline-default) [![docs](https://img.shields.io/docsrs/serde-inline-default)](https://docs.rs/serde-inline-default/latest/serde_inline_default/)

A tiny crate to set default values for serde struct fields via inline attribute declaration.

## Overview

This crate is an approach to do what [serde-rs/serde#368](https://github.com/serde-rs/serde/issues/368) purposes: Defining default values for struct fields via inline declaration instead of creating a separate function for it.

So instead of writing something like this, which can get very verbose quickly with many fields:
```rust
#[derive(Deserialize)]
struct Test {
    #[serde(default = "value_default")]
    value: u32
}

fn value_default() -> u32 { 42 }
```
you can just do this:
```rust
#[serde_inline_default]
#[derive(Deserialize)]
struct Test {
    #[serde_inline_default(42)]
    value: u32
}
```

> [!IMPORTANT]
> **`#[serde_inline_default]` must be set before `#[derive(Deserialize)]`/`#[derive(Serialize)]`!**

Internally, `#[serde_inline_default(...)]` gets expanded to a function which returns the set value and the attribute is replaced with `#[serde(default = "<function name>")]`.
So this macro is just some syntax sugar for you, but can get quite handy if you want to keep your code clean or write declarative macros / `macro_rules!`.

## Alternatives

This crate isn't perfect. Thus, you might be more satisfied with alternatives `serde` provides.

With `#[serde(default)]` + `impl Default` on a struct, `serde` uses the default implementation of the struct to get default values for each field ([docs](https://serde.rs/container-attrs.html#default)):
```rust
#[derive(Deserialize)]
#[serde(default)]
struct Test {
    value: u32
}

impl Default for Test {
    fn default() -> Self {
        Self {
            value: 42
        }
    }
}
```

If you still need/want `serde-inline-default` features, you also can combine them with `#[serde(default))` and `impl Default`:
```rust
#[serde_inline_default]
#[derive(Deserialize)]
#[serde(default)]
struct Test {
    value: u32,
    #[serde_inline_default(0)]
    other_value: u32,
}

impl Default for Test {
    fn default() -> Self {
        Self {
            value: 42,
            other_value: 42
        }
    }
}
```

## License

This project is licensed under either of the following licenses, at your option:

- Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or <http://www.apache.org/licenses/LICENSE-2.0>)
- MIT License ([LICENSE-MIT](LICENSE-MIT) or <http://opensource.org/licenses/MIT>)