core/common/src/macros.rs

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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#[macro_export]
macro_rules! variadic {
    () => (());
    (...$a:ident $(,)?) => ($a);
    (...$a:ty $(,)?) => ($a);
    ($a:ident, $($b:tt)+) => (($a, $crate::variadic!($($b)+)));
    ($a:ty, $($b:tt)+) => (($a, $crate::variadic!($($b)+)));
    ($a:ident $(,)?) => (($a, ()));
    ($a:ty $(,)?) => (($a, ()));
}