Module inverted_index 

Inverted Index for Lexical Search (Task 4)

This module implements an inverted index for BM25-based lexical search.

Structure

Term → PostingList
┌────────────────────────────────────────────────────────────────┐
│  "hello" → [(doc_1, tf=2, positions=[0,5]), (doc_3, tf=1, ...)]│
│  "world" → [(doc_1, tf=1, positions=[1]), (doc_2, tf=3, ...)] │
│  ...                                                           │
└────────────────────────────────────────────────────────────────┘

Query Execution

1. Tokenize query
2. Look up posting lists for each query term
3. Score documents using BM25
4. Return top-K results

Structs

DocumentInfo

Information about an indexed document

InvertedIndex

Inverted index for lexical search

InvertedIndexBuilder

Builder for batch index construction

Posting

A posting for a single document

PostingList

A posting list for a term

Type Aliases

DocId

Document ID type

Position

Term position in document

TermFreq

Term frequency