blob: 740dd08284fcbcf4484c09f2e9a0b9bb45a7fb60 [file] [log] [blame]
use syn::DeriveInput;
use Result;
/// Creates an instance by parsing an entire proc-macro `derive` input,
/// including the, identity, generics, and visibility of the type.
///
/// This trait should either be derived or manually implemented by a type
/// in the proc macro crate which is directly using `darling`. It is unlikely
/// that these implementations will be reusable across crates.
pub trait FromDeriveInput: Sized {
/// Create an instance from `syn::DeriveInput`, or return an error.
fn from_derive_input(input: &DeriveInput) -> Result<Self>;
}
impl FromDeriveInput for () {
fn from_derive_input(_: &DeriveInput) -> Result<Self> {
Ok(())
}
}
impl FromDeriveInput for DeriveInput {
fn from_derive_input(input: &DeriveInput) -> Result<Self> {
Ok(input.clone())
}
}