pub fn walk_flat_map_foreign_item(
vis: &mut impl MutVisitor,
item: P<ForeignItem>,
) -> SmallVec<[P<ForeignItem>; 1]>
pub fn walk_flat_map_foreign_item(
vis: &mut impl MutVisitor,
item: P<ForeignItem>,
) -> SmallVec<[P<ForeignItem>; 1]>