Inline Default

A macro for implementing Default within a struct definition. This is useful when specifying the default values within the struct definition is cleaner than separating them, for example structs with a large number fields, or when many structs are constructed. For example, ```rust use inlinedefault::inlinedefault;

inline_default! { struct KeyMap { left: char = 'h', down: char = 'j', up: char = 'k', right: char = 'l',

// uses bool::default(),
flag:   bool, 

// any constant-time expression is allowed
qwerty: bool = Keyboard::IS_QWERTY,

}} ``` expands to

```rust struct KeyMap { left: char, down: char, up: char, right: char, flag: bool, qwerty: bool, }

impl Default for KeyMap { fn default() { KeyMap { left: 'h', down: 'j', up: 'k', right: 'l', flag: bool::default(), qwerty: Keyboard::IS_QWERTY, } } } ```

Supports:

• Visibility specifiers
• Use Default if not specified
• Attributes (including derives) on both the struct and the fields
• Doc comments on both the struct and the fields
• Lifetimes and generics, with major caveats

Due to the complexity in parsing trait bounds, only a single trait bound without generics is accepted. where clauses are not supported. Specifying lifetimes are accepted, but not the 'outlives' syntax 'a: 'b. For example, the following is accepted, ```rust use inlinedefault::inlinedefault;

inline_default! { /// Example struct

[derive(Copy, Clone)]

pub(crate) struct Example<'a, T: Default> { pub a: &'a str = "example",

/// field b
b: T,

}}

but the following are not: rust use inlinedefault::inlinedefault;

// NOT VALID - too many trait bounds on T inline_default! { struct Example1 { a: T, }}

// NOT VALID - Traits bounds cannot be generic inline_default! { struct Example2> { a: T = T::from(0.0), }}

// NOT VALID - outlives syntax is not supported inline_default! { struct Example2<'a, 'b: 'a> { a: &'a str = "test", b: &'b str = "test2", }} ```

Proc Macro?

Making a proc macro would be fuller feature-wise, but I can't be bothered.