Macro rustc_data_structures::newtype_index

macro_rules! newtype_index {
    ($name:ident) => { ... };
    ($name:ident { $($tokens:tt)+ }) => { ... };
    (@derives      [$($derives:ident,)*]
     @pub          [$($pub:tt)*]
     @type         [$type:ident]
     @max          [$max:expr]
     @debug_format [$debug_format:tt]) => { ... };
    (@handle_debug
     @derives      [$($_derives:ident,)*]
     @type         [$type:ident]
     @debug_format [custom]) => { ... };
    (@handle_debug
     @derives      []
     @type         [$type:ident]
     @debug_format [$debug_format:tt]) => { ... };
    (@handle_debug
     @derives      [Debug, $($derives:ident,)*]
     @type         [$type:ident]
     @debug_format [$debug_format:tt]) => { ... };
    (@handle_debug
     @derives      [$_derive:ident, $($derives:ident,)*]
     @type         [$type:ident]
     @debug_format [$debug_format:tt]) => { ... };
    (@type         [$type:ident]
     @max          [$max:expr]
     @debug_format [$debug_format:tt]
                   pub idx
                   $($tokens:tt)*) => { ... };
    (@type         [$type:ident]
     @max          [$max:expr]
     @debug_format [$debug_format:tt]
                   $($tokens:tt)*) => { ... };
    (@pub          [$($pub:tt)*]
     @type         [$type:ident]
     @max          [$max:expr]
     @debug_format [$debug_format:tt]
                   derive [$($derives:ident),*]
                   $($tokens:tt)*) => { ... };
    (@pub          [$($pub:tt)*]
     @type         [$type:ident]
     @max          [$max:expr]
     @debug_format [$debug_format:tt]
                   derive [$($derives:ident,)+]
                   ENCODABLE = custom
                   $($tokens:tt)*) => { ... };
    (@pub          [$($pub:tt)*]
     @type         [$type:ident]
     @max          [$max:expr]
     @debug_format [$debug_format:tt]
                   derive [$($derives:ident,)+]
                   $($tokens:tt)*) => { ... };
    (@pub          [$($pub:tt)*]
     @type         [$type:ident]
     @max          [$max:expr]
     @debug_format [$debug_format:tt]
                   ENCODABLE = custom
                   $($tokens:tt)*) => { ... };
    (@pub          [$($pub:tt)*]
     @type         [$type:ident]
     @max          [$max:expr]
     @debug_format [$debug_format:tt]
                   $($tokens:tt)*) => { ... };
    (@derives      [$($derives:ident,)*]
     @pub          [$($pub:tt)*]
     @type         [$type:ident]
     @max          [$max:expr]
     @debug_format [$debug_format:tt]
                   $name:ident = $constant:expr) => { ... };
    (@derives      [$($derives:ident,)*]
     @pub          [$($pub:tt)*]
     @type         [$type:ident]
     @max          [$_max:expr]
     @debug_format [$debug_format:tt]
                   $(#[doc = $doc:expr])*
                   const $name:ident = $constant:expr) => { ... };
    (@derives      [$($derives:ident,)*]
     @pub          [$($pub:tt)*]
     @type         [$type:ident]
     @max          [$_max:expr]
     @debug_format [$debug_format:tt]
                   MAX = $max:expr,
                   $($tokens:tt)*) => { ... };
    (@derives      [$($derives:ident,)*]
     @pub          [$($pub:tt)*]
     @type         [$type:ident]
     @max          [$max:expr]
     @debug_format [$_debug_format:tt]
                   DEBUG_FORMAT = $debug_format:tt,
                   $($tokens:tt)*) => { ... };
    (@derives      [$($derives:ident,)*]
     @pub          [$($pub:tt)*]
     @type         [$type:ident]
     @max          [$max:expr]
     @debug_format [$debug_format:tt]
                   $(#[doc = $doc:expr])*
                   const $name:ident = $constant:expr,
                   $($tokens:tt)*) => { ... };
}

🔬 This is a nightly-only experimental API. (rustc_private)

this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via Cargo.toml instead?