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//! Support for nested invocations of proc-macro-hack expression macros.
//!
//! By default, macros defined through proc-macro-hack do not support nested
//! invocations, i.e. the code emitted by a proc-macro-hack macro invocation
//! cannot contain recursive calls to the same proc-macro-hack macro nor calls
//! to any other proc-macro-hack macros.
//!
//! This crate provides opt-in support for such nested invocations.
//!
//! To make a macro callable recursively, add a dependency on this crate from
//! your declaration crate and update the `#[proc_macro_hack]` re-export as
//! follows.
//!
//! ```
//! // Before
//! # const IGNORE: &str = stringify! {
//! #[proc_macro_hack]
//! pub use demo_hack_impl::add_one;
//! # };
//! ```
//!
//! ```
//! // After
//! # const IGNORE: &str = stringify! {
//! #[proc_macro_hack(support_nested)]
//! pub use demo_hack_impl::add_one;
//! # };
//! ```
//!
//! No change is required within your definition crate, only to the re-export in
//! the declaration crate.
//!
//! # Limitations
//!
//! - Nested invocations are preprocessed by a TT-muncher, so the caller's crate
//! will be required to contain `#![recursion_limit = "..."]` if there are
//! lengthy macro invocations.
//!
//! - Only up to 64 nested invocations are supported.
include!;
;
=> ;
=> ;
=> ;
=> ;
=> ;
=> ;
}