/usr/include/claw/impl/ is in libclaw-dev 1.7.4-1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/claw/impl/algorithm.tpp
/usr/include/claw/impl/automaton.tpp
/usr/include/claw/impl/avl.tpp
/usr/include/claw/impl/avl_base.tpp
/usr/include/claw/impl/basic_singleton.tpp
/usr/include/claw/impl/binary_node.tpp
/usr/include/claw/impl/bit_istream.tpp
/usr/include/claw/impl/bit_ostream.tpp
/usr/include/claw/impl/box_2d.tpp
/usr/include/claw/impl/buffered_istream.tpp
/usr/include/claw/impl/buffered_ostream.tpp
/usr/include/claw/impl/coordinate_2d.tpp
/usr/include/claw/impl/factory.tpp
/usr/include/claw/impl/game_ai.tpp
/usr/include/claw/impl/glob.tpp
/usr/include/claw/impl/graph.tpp
/usr/include/claw/impl/graph_algorithm.tpp
/usr/include/claw/impl/kmp.tpp
/usr/include/claw/impl/line_2d.tpp
/usr/include/claw/impl/lzw_decoder.tpp
/usr/include/claw/impl/lzw_encoder.tpp
/usr/include/claw/impl/max_vector.tpp
/usr/include/claw/impl/multi_type_map.tpp
/usr/include/claw/impl/multi_type_map_visitor.tpp
/usr/include/claw/impl/ordered_set.tpp
/usr/include/claw/impl/real_number.tpp
/usr/include/claw/impl/rectangle.tpp
/usr/include/claw/impl/rle_decoder.tpp
/usr/include/claw/impl/rle_encoder.tpp
/usr/include/claw/impl/smart_ptr.tpp
/usr/include/claw/impl/string_algorithm.tpp
/usr/include/claw/impl/tree.tpp
/usr/include/claw/impl/trie.tpp
/usr/include/claw/impl/vector_2d.tpp