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Diff Map Utility

A utility that takes in two Map objects, inputMap and referenceMap, and returns a new Map containing the key-value pairs in inputMap that are not present in referenceMap, or have different values in referenceMap.

How to use the utility

To use the diffMap utility, you can import it into your project like this:

import { diffMap } from '@yobta/stores'

Then, you can call the function with two Map objects as arguments:

let diffMap = diffMap(inputMap, referenceMap)

The function will return a new Map object containing the key-value pairs from inputMap that are not present in referenceMap, or have different values in referenceMap.

Output

If there are differences between the two maps, the output will be a new Map object containing the key-value pairs from inputMap that are not present in referenceMap, or have different values in referenceMap.

For example, given the following inputMap and referenceMap:

let inputMap = new Map([
  ['key1', 'value1'],
  ['key2', 'value2'],
  ['key3', 'value3'],
])
let referenceMap = new Map([
  ['key1', 'value1'],
  ['key2', 'differentValue2'],
  ['key4', 'value4'],
])

The output of diffMap(inputMap, referenceMap) would be a new Map object with the following key-value pairs:

{
'key2': 'value2',
'key3': 'value3',
}

If there are no differences between the two maps, the output will be an empty Map object.

For example, given the following inputMap and referenceMap:

let inputMap = new Map<any, any>([
  [1, 'value1'],
  [true, 'value2'],
  ['key3', false],
])
let referenceMap = new Map<any, any>([
  [1, 'value1'],
  [true, 'differentValue2'],
  ['key3', true],
])

The output of diffMap(inputMap, referenceMap) would be an empty Map object.

The diffMap utility can handle maps with different types of keys and values correctly. For example, given the following inputMap and referenceMap:

let inputMap = new Map<any, any>([
  [1, 'value1'],
  [true, 'value2'],
  ['key3', false],
])
let referenceMap = new Map<any, any>([
  [1, 'value1'],
  [true, 'differentValue2'],
  ['key3', true],
])

The output of diffMap(inputMap, referenceMap) would be a new Map object with the following key-value pairs:

{
  true: 'value2',
  'key3': false,
}