use std::slice;
/// Enum describing each component of a tantivy segment.
/// Each component is stored in its own file,
/// using the pattern `segment_uuid`.`component_extension`,
/// except the delete component that takes an `segment_uuid`.`delete_opstamp`.`component_extension`
#[derive(Copy, Clone, Eq, PartialEq)]
pub enum SegmentComponent {
/// Postings (or inverted list). Sorted lists of document ids, associated with terms
Postings,
/// Positions of terms in each document.
Positions,
/// Column-oriented random-access storage of fields.
FastFields,
/// Stores the sum of the length (in terms) of each field for each document.
/// Field norms are stored as a special u64 fast field.
FieldNorms,
/// Dictionary associating `Term`s to `TermInfo`s which is
/// simply an address into the `postings` file and the `positions` file.
Terms,
/// Row-oriented, compressed storage of the documents.
/// Accessing a document from the store is relatively slow, as it
/// requires to decompress the entire block it belongs to.
Store,
/// Temporary storage of the documents, before streamed to `Store`.
TempStore,
/// Bitset describing which document of the segment is alive.
/// (It was representing deleted docs but changed to represent alive docs from v0.17)
Delete,
}
impl SegmentComponent {
/// Iterates through the components.
pub fn iterator() -> slice::Iter<'static, SegmentComponent> {
static SEGMENT_COMPONENTS: [SegmentComponent; 8] = [
SegmentComponent::Postings,
SegmentComponent::Positions,
SegmentComponent::FastFields,
SegmentComponent::FieldNorms,
SegmentComponent::Terms,
SegmentComponent::Store,
SegmentComponent::TempStore,
SegmentComponent::Delete,
];
SEGMENT_COMPONENTS.iter()
}
}