You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: mod.rs
    path of file: ./repos/pgvecto.rs/crates/service/src/index/indexing
    
    the code of the file until where you have to start completion: pub mod flat;
pub mod hnsw;
pub mod ivf;

use self::flat::FlatIndexing;
use self::hnsw::HnswInd
    
    pub fn open(path: &Path, options: IndexOptions) -> Self {
        match options.indexing {
            IndexingOptions::Flat(_) => Self::Flat(FlatIndexing::open(path, options)),
            IndexingOptions::Ivf(_) => Self::Ivf(IvfIndexing::open(path, options)),
            IndexingOptions::Hnsw(_) => Self::Hnsw(HnswIndexing::open(path, options)),
        }
    }