how to use the extendwith function from lodash in javascript

The extendWith function from lodash is used to copy the values of all enumerable properties of one or more source objects to a destination object, while also allowing a customizer function to be called for each property.

To use extendWith in your JavaScript code, you will first need to install the lodash library. You can do this using a package manager like npm, by running the following command in your terminal:

index.tsx
npm install lodash
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Once you have installed lodash, you can use extendWith in your code by importing it from the lodash library and calling it with the appropriate arguments. Here is an example:

index.tsx
const _ = require('lodash');

const sourceObject = { a: 1, b: 2 };
const destinationObject = { b: 3, c: 4 };

_.extendWith(destinationObject, sourceObject, (objValue, srcValue) => {
  // use customizer function to only keep properties with value less than 3
  if (objValue < 3 && srcValue < 3) {
    return srcValue;
  }
});

console.log(destinationObject); // prints {b: 2, c: 4, a: 1}
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In this example, we are using extendWith to copy the properties of sourceObject to destinationObject. The customizer function is used to only keep properties with value less than 3. In this case, this means that the property "b" is kept from the destination object, and the property "a" is merged from the source object.

Note that in order to use extendWith, you will need to call it with at least two arguments: the destination object and the source object(s) to copy properties from. After these arguments, you can optionally pass a customizer function to control how the properties are merged.