Macro impl_partial_eq

macro_rules! impl_partial_eq {
    ($(
        $Type:ty $(where <$(
            $G:ident$(:
                $($Gb:ident $(<$($GbIn:ident$(=$GbInEq:ty)?)+>)?)?
                $(?$Gbq:ident)?
                $(
                    +
                    $($Gb2:ident $(<$($GbIn2:ident$(=$GbInEq2:ty)?)+>)?)?
                    $(?$Gbq2:ident)?
                )*
            )?
        ),+>)?
    ),*$(,)?) => { ... };
}