diff --git a/Cargo.toml b/Cargo.toml index 5ad65f3..abc329d 100644 --- a/Cargo.toml +++ b/Cargo.toml @@ -13,6 +13,8 @@ categories = ["encoding"] [lib] proc-macro = true +doctest = false + [dependencies] proc-macro2 = "1.0" quote = "1.0" diff --git a/src/lib.rs b/src/lib.rs index c522950..c570c62 100644 --- a/src/lib.rs +++ b/src/lib.rs @@ -5,6 +5,28 @@ use syn::{parse_macro_input, Item}; mod expand; +/// The main macro of this crate. +/// Use it to define default values of fields in structs you [`Serialize`] or [`Deserialize`]. +/// You do not need to create a extra function to provide the default value, as it is the case in serdes' implementation of default (`#[serde(default = "...")]`). +/// +/// Set this macro on a struct where you use [`Serialize`] or [`Deserialize`] and use `#[serde_inline_default(...)]` on the field you want to have a inline default value. +/// Replace the `...` with the value you want and it will be set as default if serde needs it. +/// +/// Note that you must set this macro _before_ `#[derive(Serialize)]` / `#[derive(Deserialize)]` as it wouldn't work properly if set after the derive. +/// +/// # Examples +/// +/// ```rust +/// #[serde_inline_default] +/// #[derive(Deserialize)] +/// struct Test { +/// #[serde_inline_default(42)] +/// value: u32 +/// } +/// ``` +/// +/// [`Serialize`]: https://docs.rs/serde/*/serde/trait.Serialize.html +/// [`Deserialize`]: https://docs.rs/serde/*/serde/trait.Deserialize.html #[proc_macro_attribute] pub fn serde_inline_default(_attr: TokenStream, input: TokenStream) -> TokenStream { let item = parse_macro_input!(input as Item);