2018-04-30 01:42:46 -07:00

26 lines
898 B
Rust

use proc_macro2::{Op, Spacing};
use quote::Tokens;
// None of our generated code requires the `From::from` error conversion
// performed by the standard library's `try!` macro. With this simplified macro
// we see a significant improvement in type checking and borrow checking time of
// the generated code and a slight improvement in binary size.
pub fn replacement() -> Tokens {
// Cannot pass `$expr` to `quote!` prior to Rust 1.17.0 so interpolate it.
let dollar = Op::new('$', Spacing::Alone);
quote! {
#[allow(unused_macros)]
macro_rules! try {
(#dollar __expr:expr) => {
match #dollar __expr {
_serde::export::Ok(__val) => __val,
_serde::export::Err(__err) => {
return _serde::export::Err(__err);
}
}
}
}
}
}