# Indexing

# Fuse.createIndex

Pre-generate the index from the list, and pass it directly into the Fuse instance. If the list is (considerably) large, it speed up instantiation.

Example

const books = [
  {
    title: "Old Man's War",
    author: {
      firstName: 'John',
      lastName: 'Scalzi'
    }
  },
  {
    title: 'The Lock Artist',
    author: {
      firstName: 'Steve',
      lastName: 'Hamilton'
    }
  }
  /*...*/
]

const options = { keys: ['title', 'author.firstName'] }

// Create the Fuse index
const myIndex = Fuse.createIndex(options.keys, books)
// initialize Fuse with the index
const fuse = new Fuse(books, options, myIndex)

TIP

Fuse will automatically index the table if one isn't provided during instantiation.

# Fuse.parseIndex

Parses a serialized Fuse index.

Example

// (1) In the build step
// Create the Fuse index
const myIndex = Fuse.createIndex(['title', 'author.firstName'], books)
// Serialize and save it
fs.writeFile('fuse-index.json', JSON.stringify(myIndex.toJSON()))

// (2) When app starts
// Load and deserialize index
const fuseIndex = await require('fuse-index.json')
const myIndex = Fuse.parseIndex(fuseIndex)
// initialize Fuse with the index
const fuse = new Fuse(books, options, myIndex)