compress_alignment a = (compressed, counts, mapping) where ca = builtin_compress_alignment a
                                                           compressed = get_vector_index ca 0
                                                           counts = get_vector_index ca 1
                                                           mapping = get_vector_index ca 2
compress_alignment a = (compressed, counts, mapping) where ca = builtin_compress_alignment a
                                                           compressed = get_vector_index ca 0
                                                           counts = get_vector_index ca 1
                                                           mapping = get_vector_index ca 2
compress_alignment a = (compressed, counts, mapping) where ca = builtin_compress_alignment a
                                                           compressed = get_vector_index ca 0
                                                           counts = get_vector_index ca 1
                                                           mapping = get_vector_index ca 2