v0.3.0

Features

Tagged Tuple Structs

Tuple structs can now be tagged with #[attr_args] which allows for attributes using unnamed parameters.

Example

#[attr_args]
struct Foo (String);

#[foo("Value")]
fn bar() {
    //...
}

Tagged Enums

Now users can use the #[attr_args] attribute on enums to allow for custom attributes that have multiple forms.

Example

#[attr_args]
enum Foo {
    Both { first: String, second: String },
    FirstOnly { first: String },
    UnnamedFirstOnly(String),
    SecondOnly { second: String }
}

#[foo(first = "First", second = "Second")] // Valid
#[foo(first = "First")] // Valid
#[foo("First")] // Valid
#[foo(second = "Second")] // Valid
#[foo()] // Invalid
fn bar() {
    //...
}