macro_rules! impl_binop {
($struct_name:ident, $arg1_type:ty, $arg2_type:ty, $out_type:ty, $op:ident, $feature_flag:expr) => { ... };
}macro_rules! impl_binop {
($struct_name:ident, $arg1_type:ty, $arg2_type:ty, $out_type:ty, $op:ident, $feature_flag:expr) => { ... };
}