MeiliSearch/raptor/src/lib.rs
2018-09-09 11:13:58 +02:00

103 lines
2.8 KiB
Rust

#[macro_use] extern crate lazy_static;
pub mod rank;
pub mod metadata;
pub mod automaton;
pub use self::metadata::{
Metadata, MetadataBuilder,
Stream, StreamBuilder,
Union, OpBuilder,
IndexedValues,
};
pub use self::rank::RankedStream;
pub type DocumentId = u64;
/// This structure represent the position of a word
/// in a document and its attributes.
///
/// This is stored in the map, generated at index time,
/// extracted and interpreted at search time.
#[derive(Debug, Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Hash)]
#[repr(C)]
pub struct DocIndex {
/// The document identifier where the word was found.
pub document: DocumentId,
/// The attribute identifier in the document
/// where the word was found.
///
/// This is an `u8` therefore a document
/// can not have more than `2^8` attributes.
pub attribute: u8,
/// The index where the word was found in the attribute.
///
/// Only the first 1000 words are indexed.
pub attribute_index: u32,
}
/// This structure represent a matching word with informations
/// on the location of the word in the document.
///
/// The order of the field is important because it defines
/// the way these structures are ordered between themselves.
///
/// The word in itself is not important.
// TODO do data oriented programming ? very arrays ?
#[derive(Debug, Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Hash)]
pub struct Match {
/// The word index in the query sentence.
/// Same as the `attribute_index` but for the query words.
///
/// Used to retrieve the automaton that match this word.
pub query_index: u32,
/// The distance the word has with the query word
/// (i.e. the Levenshtein distance).
pub distance: u8,
/// The attribute in which the word is located
/// (i.e. Title is 0, Description is 1).
///
/// This is an `u8` therefore a document
/// can not have more than `2^8` attributes.
pub attribute: u8,
/// Where does this word is located in the attribute string
/// (i.e. at the start or the end of the attribute).
///
/// The index in the attribute is limited to a maximum of `2^32`
/// this is because we index only the first 1000 words
/// in an attribute.
pub attribute_index: u32,
/// Whether the word that match is an exact match or a prefix.
pub is_exact: bool,
}
impl Match {
pub fn zero() -> Self {
Match {
query_index: 0,
distance: 0,
attribute: 0,
attribute_index: 0,
is_exact: false,
}
}
pub fn max() -> Self {
Match {
query_index: u32::max_value(),
distance: u8::max_value(),
attribute: u8::max_value(),
attribute_index: u32::max_value(),
is_exact: true,
}
}
}