Macro cbor

macro_rules! cbor {
    (@map {$($key:expr => $val:expr),*} $(,)?) => { ... };
    (@map {$($key:expr => $val:expr),*} { $($nkey:tt)* } => $($next:tt)*) => { ... };
    (@map {$($key:expr => $val:expr),*} [ $($nkey:tt)* ] => $($next:tt)*) => { ... };
    (@map {$($key:expr => $val:expr),*} $nkey:expr => { $($nval:tt)* }, $($next:tt)*) => { ... };
    (@map {$($key:expr => $val:expr),*} $nkey:expr => [ $($nval:tt)* ], $($next:tt)*) => { ... };
    (@map {$($key:expr => $val:expr),*} $nkey:expr => $nval:expr, $($next:tt)*) => { ... };
    (@seq [$($val:expr),*] $(,)?) => { ... };
    (@seq [$($val:expr),*] { $($item:tt)* }, $($next:tt)*) => { ... };
    (@seq [$($val:expr),*] [ $($item:tt)* ], $($next:tt)*) => { ... };
    (@seq [$($val:expr),*] $item:expr, $($next:tt)*) => { ... };
    ({ $($next:tt)* }) => { ... };
    ([ $($next:tt)* ]) => { ... };
    ($val:expr) => { ... };
}

Build a Value conveniently.

The syntax should be intuitive if you are familiar with JSON. You can also inline simple Rust expressions, including custom values that implement serde::Serialize. Note that this macro returns Result<Value, Error>, so you should handle the error appropriately.

use ciborium::cbor;

let value = cbor!({
    "code" => 415,
    "message" => null,
    "continue" => false,
    "extra" => { "numbers" => [8.2341e+4, 0.251425] },
}).unwrap();