Macro quick_error::quick_error

macro_rules! quick_error {
    (   $(#[$meta:meta])*
        pub enum $name:ident { $($chunks:tt)* }
    ) => { ... };
    (   $(#[$meta:meta])*
        enum $name:ident { $($chunks:tt)* }
    ) => { ... };
    (   $(#[$meta:meta])*
        pub enum $name:ident wraps $enum_name:ident { $($chunks:tt)* }
    ) => { ... };
    (   $(#[$meta:meta])*
        pub enum $name:ident wraps pub $enum_name:ident { $($chunks:tt)* }
    ) => { ... };
    (   $(#[$meta:meta])*
        enum $name:ident wraps $enum_name:ident { $($chunks:tt)* }
    ) => { ... };
    (   $(#[$meta:meta])*
        enum $name:ident wraps pub $enum_name:ident { $($chunks:tt)* }
    ) => { ... };
    (
        WRAPPER $internal:ident [ $($strdef:tt)* ] $strname:ident
        $(#[$meta:meta])*
    ) => { ... };
    (SORT [enum $name:ident $( #[$meta:meta] )*]
        items [$($( #[$imeta:meta] )*
                  => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
                                {$( $ifuncs:tt )*} )* ]
        buf [ ]
        queue [ ]
    ) => { ... };
    (SORT [pub enum $name:ident $( #[$meta:meta] )*]
        items [$($( #[$imeta:meta] )*
                  => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
                                {$( $ifuncs:tt )*} )* ]
        buf [ ]
        queue [ ]
    ) => { ... };
    (SORT [$( $def:tt )*]
        items [$($( #[$imeta:meta] )*
                  => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
                                {$( $ifuncs:tt )*} )* ]
        buf [$( #[$bmeta:meta] )*]
        queue [ #[$qmeta:meta] $( $tail:tt )*]
    ) => { ... };
    (SORT [$( $def:tt )*]
        items [$($( #[$imeta:meta] )*
                  => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
                                {$( $ifuncs:tt )*} )* ]
        buf [$( #[$bmeta:meta] )*]
        queue [ $qitem:ident $( $tail:tt )*]
    ) => { ... };
    (SORT [$( $def:tt )*]
        items [$($( #[$imeta:meta] )*
                  => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
                                {$( $ifuncs:tt )*} )* ]
        buf [$( #[$bmeta:meta] )*
            => $bitem:ident: $bmode:tt [$( $bvar:ident: $btyp:ty ),*] ]
        queue [ #[$qmeta:meta] $( $tail:tt )*]
    ) => { ... };
    (SORT [$( $def:tt )*]
        items [$($( #[$imeta:meta] )*
                  => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
                                {$( $ifuncs:tt )*} )* ]
        buf [$( #[$bmeta:meta] )* => $bitem:ident: UNIT [ ] ]
        queue [($( $qvar:ident: $qtyp:ty ),+) $( $tail:tt )*]
    ) => { ... };
    (SORT [$( $def:tt )*]
        items [$($( #[$imeta:meta] )*
                  => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
                                {$( $ifuncs:tt )*} )* ]
        buf [$( #[$bmeta:meta] )* => $bitem:ident: UNIT [ ] ]
        queue [{ $( $qvar:ident: $qtyp:ty ),+} $( $tail:tt )*]
    ) => { ... };
    (SORT [$( $def:tt )*]
        items [$($( #[$imeta:meta] )*
                  => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
                                {$( $ifuncs:tt )*} )* ]
        buf [$( #[$bmeta:meta] )* => $bitem:ident: UNIT [ ] ]
        queue [{$( $qvar:ident: $qtyp:ty ),+ ,} $( $tail:tt )*]
    ) => { ... };
    (SORT [$( $def:tt )*]
        items [$($( #[$imeta:meta] )*
                  => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
                                {$( $ifuncs:tt )*} )* ]
        buf [$( #[$bmeta:meta] )*
                 => $bitem:ident: $bmode:tt [$( $bvar:ident: $btyp:ty ),*] ]
        queue [ {$( $qfuncs:tt )*} $( $tail:tt )*]
    ) => { ... };
    (SORT [$( $def:tt )*]
        items [$($( #[$imeta:meta] )*
                  => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
                                {$( $ifuncs:tt )*} )* ]
        buf [$( #[$bmeta:meta] )*
                 => $bitem:ident: $bmode:tt [$( $bvar:ident: $btyp:ty ),*] ]
        queue [ $qitem:ident $( $tail:tt )*]
    ) => { ... };
    (SORT [$( $def:tt )*]
        items [$($( #[$imeta:meta] )*
                  => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
                                {$( $ifuncs:tt )*} )* ]
        buf [$( #[$bmeta:meta] )*
            => $bitem:ident: $bmode:tt [$( $bvar:ident: $btyp:ty ),*] ]
        queue [ ]
    ) => { ... };
    (ENUM_DEFINITION [pub enum $name:ident $( #[$meta:meta] )*]
        body [$($( #[$imeta:meta] )*
            => $iitem:ident ($(($( $ttyp:ty ),+))*) {$({$( $svar:ident: $styp:ty ),*})*} )* ]
        queue [ ]
    ) => { ... };
    (ENUM_DEFINITION [enum $name:ident $( #[$meta:meta] )*]
        body [$($( #[$imeta:meta] )*
            => $iitem:ident ($(($( $ttyp:ty ),+))*) {$({$( $svar:ident: $styp:ty ),*})*} )* ]
        queue [ ]
    ) => { ... };
    (ENUM_DEFINITION [$( $def:tt )*]
        body [$($( #[$imeta:meta] )*
            => $iitem:ident ($(($( $ttyp:ty ),+))*) {$({$( $svar:ident: $styp:ty ),*})*} )* ]
        queue [$( #[$qmeta:meta] )*
            => $qitem:ident: UNIT [ ] $( $queue:tt )*]
    ) => { ... };
    (ENUM_DEFINITION [$( $def:tt )*]
        body [$($( #[$imeta:meta] )*
            => $iitem:ident ($(($( $ttyp:ty ),+))*) {$({$( $svar:ident: $styp:ty ),*})*} )* ]
        queue [$( #[$qmeta:meta] )*
            => $qitem:ident: TUPLE [$( $qvar:ident: $qtyp:ty ),+] $( $queue:tt )*]
    ) => { ... };
    (ENUM_DEFINITION [$( $def:tt )*]
        body [$($( #[$imeta:meta] )*
            => $iitem:ident ($(($( $ttyp:ty ),+))*) {$({$( $svar:ident: $styp:ty ),*})*} )* ]
        queue [$( #[$qmeta:meta] )*
            => $qitem:ident: STRUCT [$( $qvar:ident: $qtyp:ty ),*] $( $queue:tt )*]
    ) => { ... };
    (IMPLEMENTATIONS
        $name:ident {$(
            $item:ident: $imode:tt [$(#[$imeta:meta])*] [$( $var:ident: $typ:ty ),*] {$( $funcs:tt )*}
        )*}
    ) => { ... };
    (FIND_DISPLAY_IMPL $name:ident $item:ident: $imode:tt
        { display($self_:tt) -> ($( $exprs:tt )*) $( $tail:tt )*}
    ) => { ... };
    (FIND_DISPLAY_IMPL $name:ident $item:ident: $imode:tt
        { display($pattern:expr) $( $tail:tt )*}
    ) => { ... };
    (FIND_DISPLAY_IMPL $name:ident $item:ident: $imode:tt
        { display($pattern:expr, $( $exprs:tt )*) $( $tail:tt )*}
    ) => { ... };
    (FIND_DISPLAY_IMPL $name:ident $item:ident: $imode:tt
        { $t:tt $( $tail:tt )*}
    ) => { ... };
    (FIND_DISPLAY_IMPL $name:ident $item:ident: $imode:tt
        { }
    ) => { ... };
    (FIND_DESCRIPTION_IMPL $item:ident: $imode:tt $me:ident $fmt:ident
        [$( $var:ident ),*]
        { description($expr:expr) $( $tail:tt )*}
    ) => { ... };
    (FIND_DESCRIPTION_IMPL $item:ident: $imode:tt $me:ident $fmt:ident
        [$( $var:ident ),*]
        { $t:tt $( $tail:tt )*}
    ) => { ... };
    (FIND_DESCRIPTION_IMPL $item:ident: $imode:tt $me:ident $fmt:ident
        [$( $var:ident ),*]
        { }
    ) => { ... };
    (FIND_CAUSE_IMPL $item:ident: $imode:tt
        [$( $var:ident ),*]
        { cause($expr:expr) $( $tail:tt )*}
    ) => { ... };
    (FIND_CAUSE_IMPL $item:ident: $imode:tt
        [$( $var:ident ),*]
        { $t:tt $( $tail:tt )*}
    ) => { ... };
    (FIND_CAUSE_IMPL $item:ident: $imode:tt
        [$( $var:ident ),*]
        { }
    ) => { ... };
    (FIND_FROM_IMPL $name:ident $item:ident: $imode:tt
        [$( $var:ident: $typ:ty ),*]
        { from() $( $tail:tt )*}
    ) => { ... };
    (FIND_FROM_IMPL $name:ident $item:ident: UNIT
        [ ]
        { from($ftyp:ty) $( $tail:tt )*}
    ) => { ... };
    (FIND_FROM_IMPL $name:ident $item:ident: TUPLE
        [$( $var:ident: $typ:ty ),*]
        { from($fvar:ident: $ftyp:ty) -> ($( $texpr:expr ),*) $( $tail:tt )*}
    ) => { ... };
    (FIND_FROM_IMPL $name:ident $item:ident: STRUCT
        [$( $var:ident: $typ:ty ),*]
        { from($fvar:ident: $ftyp:ty) -> {$( $tvar:ident: $texpr:expr ),*} $( $tail:tt )*}
    ) => { ... };
    (FIND_FROM_IMPL $name:ident $item:ident: $imode:tt
        [$( $var:ident: $typ:ty ),*]
        { $t:tt $( $tail:tt )*}
    ) => { ... };
    (FIND_FROM_IMPL $name:ident $item:ident: $imode:tt
        [$( $var:ident: $typ:ty ),*]
        { }
    ) => { ... };
    (FIND_CONTEXT_IMPL $name:ident $item:ident: TUPLE
        [$( $var:ident: $typ:ty ),*]
        { context($cvar:ident: AsRef<$ctyp:ty>, $fvar:ident: $ftyp:ty)
            -> ($( $texpr:expr ),*) $( $tail:tt )* }
    ) => { ... };
    (FIND_CONTEXT_IMPL $name:ident $item:ident: TUPLE
        [$( $var:ident: $typ:ty ),*]
        { context($cvar:ident: $ctyp:ty, $fvar:ident: $ftyp:ty)
            -> ($( $texpr:expr ),*) $( $tail:tt )* }
    ) => { ... };
    (FIND_CONTEXT_IMPL $name:ident $item:ident: STRUCT
        [$( $var:ident: $typ:ty ),*]
        { context($cvar:ident: AsRef<$ctyp:ty>, $fvar:ident: $ftyp:ty)
            -> {$( $tvar:ident: $texpr:expr ),*} $( $tail:tt )* }
    ) => { ... };
    (FIND_CONTEXT_IMPL $name:ident $item:ident: STRUCT
        [$( $var:ident: $typ:ty ),*]
        { context($cvar:ident: $ctyp:ty, $fvar:ident: $ftyp:ty)
            -> {$( $tvar:ident: $texpr:expr ),*} $( $tail:tt )* }
    ) => { ... };
    (FIND_CONTEXT_IMPL $name:ident $item:ident: $imode:tt
        [$( $var:ident: $typ:ty ),*]
        { $t:tt $( $tail:tt )*}
    ) => { ... };
    (FIND_CONTEXT_IMPL $name:ident $item:ident: $imode:tt
        [$( $var:ident: $typ:ty ),*]
        { }
    ) => { ... };
    (ITEM_BODY $(#[$imeta:meta])* $item:ident: UNIT
    ) => { ... };
    (ITEM_BODY $(#[$imeta:meta])* $item:ident: TUPLE
        [$( $typ:ty ),*]
    ) => { ... };
    (ITEM_BODY $(#[$imeta:meta])* $item:ident: STRUCT
        [$( $var:ident: $typ:ty ),*]
    ) => { ... };
    (ITEM_PATTERN $name:ident $item:ident: UNIT []
    ) => { ... };
    (ITEM_PATTERN $name:ident $item:ident: TUPLE
        [$( ref $var:ident ),*]
    ) => { ... };
    (ITEM_PATTERN $name:ident $item:ident: STRUCT
        [$( ref $var:ident ),*]
    ) => { ... };
    (ERROR_CHECK $imode:tt display($self_:tt) -> ($( $exprs:tt )*) $( $tail:tt )*) => { ... };
    (ERROR_CHECK $imode:tt display($pattern: expr) $( $tail:tt )*) => { ... };
    (ERROR_CHECK $imode:tt display($pattern: expr, $( $exprs:tt )*) $( $tail:tt )*) => { ... };
    (ERROR_CHECK $imode:tt description($expr:expr) $( $tail:tt )*) => { ... };
    (ERROR_CHECK $imode:tt cause($expr:expr) $($tail:tt)*) => { ... };
    (ERROR_CHECK $imode:tt from() $($tail:tt)*) => { ... };
    (ERROR_CHECK $imode:tt from($ftyp:ty) $($tail:tt)*) => { ... };
    (ERROR_CHECK TUPLE from($fvar:ident: $ftyp:ty) -> ($( $e:expr ),*) $( $tail:tt )*) => { ... };
    (ERROR_CHECK STRUCT from($fvar:ident: $ftyp:ty) -> {$( $v:ident: $e:expr ),*} $( $tail:tt )*) => { ... };
    (ERROR_CHECK TUPLE context($cvar:ident: $ctyp:ty, $fvar:ident: $ftyp:ty)
        -> ($( $e:expr ),*) $( $tail:tt )*) => { ... };
    (ERROR_CHECK STRUCT context($cvar:ident: $ctyp:ty, $fvar:ident: $ftyp:ty)
        -> {$( $v:ident: $e:expr ),*} $( $tail:tt )*) => { ... };
    (ERROR_CHECK $imode:tt ) => { ... };
    (IDENT $ident:ident) => { ... };
}

Main macro that does all the work