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//! An internal crate to support auto_enums - **do not use directly**

#![doc(test(
    no_crate_inject,
    attr(
        deny(warnings, rust_2018_idioms, single_use_lifetimes),
        allow(dead_code, unused_variables)
    )
))]
#![forbid(unsafe_code)]
#![warn(future_incompatible, rust_2018_idioms, single_use_lifetimes, unreachable_pub)]
#![warn(clippy::all, clippy::default_trait_access)]

#[cfg(all(feature = "generator_trait", not(feature = "unstable")))]
compile_error!(
    "The `generator_trait` feature requires the `unstable` feature as an explicit opt-in to unstable features"
);

#[cfg(all(feature = "fn_traits", not(feature = "unstable")))]
compile_error!(
    "The `fn_traits` feature requires the `unstable` feature as an explicit opt-in to unstable features"
);

#[cfg(all(feature = "trusted_len", not(feature = "unstable")))]
compile_error!(
    "The `trusted_len` feature requires the `unstable` feature as an explicit opt-in to unstable features"
);

// older compilers require explicit `extern crate`.
#[allow(unused_extern_crates)]
extern crate proc_macro;

#[macro_use]
mod utils;

mod derive;
mod enum_derive;

use proc_macro::TokenStream;

/// An attribute macro like a wrapper of `#[derive]`, implementing
/// the supported traits and passing unsupported traits to `#[derive]`.
///
/// See crate level documentation for details.
#[proc_macro_attribute]
pub fn enum_derive(args: TokenStream, input: TokenStream) -> TokenStream {
    crate::enum_derive::attribute(args.into(), input.into()).into()
}