how to use the mergewith function from the lodash library in typescript

To use the mergeWith() function from the Lodash library in Typescript, follow these steps:

1. Install Lodash via npm:

npm install lodash
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2. Import the mergeWith() function from Lodash:

index.ts
import mergeWith from 'lodash/mergeWith';
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3. Define your objects that you want to merge. Here's an example:

index.ts
const obj1 = { a: [{ b: 2 }, { d: 4 }] };
const obj2 = { a: [{ c: 3 }, { e: 5 }] };
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4. Define a customizer function that receives the values of each property and returns the value to use in the merged object. Here's an example that concatenates arrays:

index.ts
const customizer = (objValue, srcValue) => {
  if (Array.isArray(objValue)) {
    return objValue.concat(srcValue);
  }
}
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5. Call the mergeWith() function with the objects and the customizer function:

index.ts
const result = mergeWith(obj1, obj2, customizer);
console.log(result);
// Output: { a: [{ b: 2, c: 3 }, { d: 4, e: 5 }] }
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The resulting merged object will have all the properties from both objects, with arrays concatenated instead of overwritten.