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: planning.rs
    path of file: ./repos/pgvecto.rs/src/gucs
    
    the code of the file until where you have to start completion: use pgrx::{GucContext, GucFlags, GucRegistry, GucSetting};

#[derive(Debug, Clone, Copy, pgrx::PostgresGucEnum)]
#[allow(non_camel_case_types)]
pub enum Mode {
    basic,
    vbase,
}

pub static ENABLE_INDEX: GucSetting<bool> = G
    
pub unsafe fn init() {
    GucRegistry::define_bool_guc(
        "vectors.enable_index",
        "Enables or disables the query planner's use of vector index-scan plan types.",
        "https://docs.pgvecto.rs/usage/search.html",
        &ENABLE_INDEX,
        GucContext::Userset,
        GucFlags::default(),
    );
    GucRegistry::define_enum_guc(
        "vectors.search_mode",
        "Search mode.",
        "https://docs.pgvecto.rs/usage/search.html",
        &SEARCH_MODE,
        GucContext::Userset,
        GucFlags::default(),
    );
    GucRegistry::define_bool_guc(
        "vectors.pgvector_compatibility",
        "Enables or disables pgvector compatibility mode.",
        "https://docs.pgvecto.rs/usage/compatibility.html",
        &ENABLE_PGVECTOR_COMPATIBILITY,
        GucContext::Userset,
        GucFlags::default(),
    )
}