@maxhusky/indexmap v1.0.0

class IndexMap

A map that uses binary search

Constructors

new IndexMap(sortedArrays = [keys[], values[]])

• sortedArrays {[]} OPTIONAL An array of two aligned array where the first are the keys and the second are the values. The keys must be aligned to their values and must be sorted in ascending order.
  • keys {Key[]} An array of keys.
  • values {Value[]} An array of values.

IndexMap.fromArray(keys, [sorted=false])

Creates an IndexMap from an array of keys.

• keys {Key[]} An array of keys to add to the Index.
• sorted {boolean} OPTIONAL Indicates if the array is sorted in ascending order. Default: false.

IndexMap.fromMap(mapLike, [sorted=false])

Creates an IndexMap from a map like object

• mapLike {Map<Key, Value>}
• sorted {boolean} OPTIONAL Indicates if the map has its keys sorted in ascending order. Default: false.

Properties

length {number} READONLY

The number of items in the IndexMap.

Methods

set(key, [value=undefined]): void

Sets a key to a given value.

• key {Key} The key to set.
• value {Value|undefined} OPTIONAL The value to set the key to.

get(key): Value|undefined

Gets the value assigned to the given key.

• key {Key} The key to find the value of.

  Returns {Value|undefined} the value or undefined if no key was found.

delete(key): Value|undefined

Deletes a key from the IndexMap.

• key {Key} The key to delete.

  Returns {Value|undefined} the value of the deleted key or undefined if no key was found/deleted.

getRange(min, max): Value[]

Gets all the values in the given range (inclusive).

• min {Key} the smallest allowed key.

• max {Key} the largest allowed key.

  Returns {Value[]} the values that fit within the key range.

size(): number

Returns {number} the number of items in the IndexMap.

toString(): string

Returns {string} a string representing the IndexMap

toJSON(): [Key[],Value[]]

Returns {[Key[],Value[]]} an array of parallel arrays representing the key/value pairs of the IndexMap

Iterator

The iterator yields an array containing a key:pair. The first value is the key and the second value is its value. The iterator is auto updating to changes in the IndexMap however will skip any key pairs where the key is less then or equal to the last returned key.

Example

const sortedArrays = [['a', 'b', 'c', 'd'],
                      [  1,   3,   4,   0]];
var im = new IndexMap(sortedArrays);
for (let p of im) {
  console.log('key: ' + p[0]);
  console.log('value: ' + p[1]);
}
// prints:
//key: a
//value: 1
//key: b
//value: 3
//key: c
//value: 4
//key: d
//value: 0