how to use the ismap function from the underscore library in typescript

To use the ismap function from the Underscore library in TypeScript, you need to first install Underscore.

npm install underscore
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Then, you can import the ismap function from Underscore and use it in your TypeScript code like this:

index.ts
import * as _ from 'underscore';

const map = _.map([1, 2, 3], (num) => num * 2);
console.log(map); // [2, 4, 6]

const obj = {
  one: 1,
  two: 2
};

const mapObj = _.map(obj, (value, key) => key + '=' + value);
console.log(mapObj); // ["one=1", "two=2"]

const isMapArray = _.map([true, false, true], _.ismap);
console.log(isMapArray); // [false, false, false]

const isMapObject = _.map({one: true, two: false}, _.ismap);
console.log(isMapObject); // [true, true]
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In the above code, we first import the map function and the ismap function from Underscore. We then use the map function to apply the ismap function to an array and an object. The ismap function returns true when its argument is a map object (an object where the keys are strings and the values are arbitrary values), and false otherwise. The resulting arrays isMapArray and isMapObject contain the result of applying ismap to each element of the original arrays.