#generics #macro-rules #parser #macro #where

no-std generics2

Provides macros for parsing generics (with optional where clause) in macro_rules! - enhanced fork of generics

1 unstable release

0.3.3 Jan 23, 2022

#2649 in Rust patterns

39 downloads per month
Used in deptypes

MIT/Apache

51KB
1.5K SLoC

generics2

Provides macros for parsing generics and where clauses in macro_rules!.

pub trait TheTrait { }

#[doc(hidden)]
pub use generics2::parse as generics_parse;
#[doc(hidden)]
pub use std::compile_error as std_compile_error;

#[macro_export]
macro_rules! impl_the_trait {
    (
        $name:ident $($token:tt)*
    ) => {
        $crate::generics_parse! {
            $crate::impl_the_trait {
                @impl $name
            }
            $($token)*
        }
    };
    (
        @impl $name:ident [$($g:tt)*] [$($r:tt)*] [$($w:tt)*]
    ) => {
        impl $($g)* $crate::TheTrait for $name $($r)* $($w)* { }
    };
    (
        @impl $name:ident [$($g:tt)*] [$($r:tt)*] [$($w:tt)*] $($token:tt)+ 
    ) => {
        $crate::std_compile_error!(
            "invalid input, allowed input is '$name $( < $generics > $(where $where_clause)? )?'"
        );
    };
}

No runtime deps