sval_derive 2.19.0

Derive support for sval
Documentation 
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/*!
`#![derive(Value)]`.

This library hosts a custom-derive to simplify implementing `sval::Value`.

# Structs

Container attributes:

- `#[sval(tag = "path::to::TAG")]`: Set a tag on the struct. No tag is used by default.
- `#[sval(label = "text")]`: Set a label on the struct. The identifier of the struct is used by default.
- `#[sval(index = 1)]`: Set an index on the struct. No index is used by default.
- `#[sval(unlabeled_fields)]`: Specify that all fields should be unlabeled. This will stream the struct as a tuple.
If `#[sval(unindexed_fields)]` is also specified then it will stream the struct as a sequence.
- `#[sval(unindexed_fields]`: Specify that all fields should be unindexed. This will stream the struct as a record.
If `#[sval(unlabeled_fields)]` is also specified then it will stream the struct as a sequence.

Field attributes:

- `#[sval(tag = "path::to::TAG")]`: Set a tag on the struct field itself. No tag is used by default.
If you want to use a tag to signal that the field's value has a particular property then use `#[sval(data_tag)]`.
- `#[sval(data_tag = "path::to::TAG")]`: Set a tag on the struct field's value. No tag is used by default.
- `#[sval(label = "text")]`: Set a label on the struct field. The identifier of the field is used by default.
- `#[sval(index = 1)]`: Set an index on the struct field. The zero-based offset of the field is used by default.
- `#[sval(skip)]`: Skip a field.
- `#[sval(flatten)]`: Flatten the field onto the struct. This attribute requires the `flatten` Cargo feature.

# Newtypes

Container attributes:

- `#[sval(tag = "path::to::TAG")]`: Set a tag on the newtype. No tag is used by default.
- `#[sval(label = "text")]`: Set a label on the newtype. The identifier of the newtype is used by default.
- `#[sval(index = 1)]`: Set an index on the newtype. No index is used by default.
- `#[sval(transparent)]`: Stream the newtype as its underlying field without wrapping it.

# Enums

Container attributes:

- `#[sval(tag = "path::to::TAG")]`: Set a tag on the enum. No tag is used by default.
- `#[sval(label = "text")]`: Set a label on the enum. The identifier of the enum is used by default.
- `#[sval(index = 1)]`: Set an index on the enum. No index is used by default.
- `#[sval(dynamic)]`: Stream the variant without wrapping it in an enum.

Variant attributes:

- `#[sval(tag = "path::to::TAG")]`: Set a tag on the enum variant itself. No tag is used by default.
- `#[sval(label = "text")]`: Set a label on the enum variant. The identifier of the variant is used by default.
- `#[sval(index = 1)]`: Set an index on the enum variant. The zero-based offset of the variant is used by default.

# `sval_ref::ValueRef`

Add the `#[sval(ref)]` attribute alongside `#[derive(sval::Value)]` to generate a `sval_ref::ValueRef` impl in addition to `sval::Value`.
The lifetime is inferred from the type's single lifetime parameter.
Use `#[sval(ref = "'a")]` to specify an explicit lifetime, or `#[sval(ref = "'b where 'b: 'a")]` to add bounds.

Field attributes (requires the `ref` Cargo feature):

- `#[sval(outer_ref)]`: Stream an external reference type, like `&'sval T`, by dereferencing its binding (`stream.value(*field)`).
- `#[sval(inner_ref)]`: Stream an internal reference type, like `T<'sval>`, via its `ValueRef::stream_ref()` implementation.
- `#[sval(computed)]`: Stream the field by value via `stream.value_computed(field)`.

Fields are streamed in `sval_ref::ValueRef` **as computed** by default. Use either the `#[sval(outer_ref)]` or `#[sval(inner_ref)]` attributes to pick a borrowing strategy.
*/

#![doc(html_logo_url = "https://raw.githubusercontent.com/sval-rs/sval/main/asset/logo.svg")]

#[doc(inline)]
pub use sval_derive_macros::*;

pub mod extensions {
    #[cfg(feature = "flatten")]
    pub use sval_flatten as flatten;

    #[cfg(feature = "ref")]
    pub use sval_ref as r#ref;
}