how to use the assigninwith function from lodash in javascript

The assigninWith() function from the Lodash library is used to merge two or more objects with custom logic. It is similar to the assign() function, but it allows you to specify a custom function for handling the merge of properties.

Here's an example of how to use the assigninWith() function:

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

const obj1 = {
  a: 1,
  b: 2
};

const obj2 = {
  b: 3,
  c: 4
};

const customizer = (objValue, srcValue) => {
  if (_.isArray(objValue)) {
    return objValue.concat(srcValue);
  }
};

const result = _.assigninWith(obj1, obj2, customizer);

console.log(result); // { a: 1, b: [2, 3], c: 4 }
324 chars
22 lines

In this example, we have two objects obj1 and obj2. We also have a customizer function that checks if the property being merged is an array. If it is, it concatenates the two arrays.

We then call the assigninWith() function with the two objects and the customizer function as arguments. The result is an object that merges the properties of obj1 and obj2 based on the rules specified in the customizer function.