Omit functions from category

Question

Omit functions from category

This question reminds me of another question I came across, but it's not quite the same and I'm still struggling to figure it out.

Basically, I need to duplicate a data structure but remove all the methods from it.

interface XYZ {
  x: number;
  y: string;
  z(): void;
}

So in this case, I want to exclude the method z and end up with:

interface XY {
  x: number;
  y: string;
}

I am aware that I can use the Omit utility type like this:

type OmitZ = Omit<XYZ, "z">;

However, I actually want to omit based on property type rather than key string. Is there a way to achieve this?

typescript

Answer 1

Answer №1

Give this a shot:


const ExcludeFunctions = <T>(obj: T) => {
  const newObj = {} as { [K in keyof T]: T[K] extends Function ? never : K };
  
  for (const key in obj) {
    if (!(obj[key] instanceof Function)) {
      newObj[key] = obj[key];
    }
  }

  return newObj;
};

const result = ExcludeFunctions({ name: "John", age: 30, sayHello: () => console.log("Hello") });

console.log(result); // Output: { name: "John", age: 30 }

Answer 2

Give this a shot:


const ExcludeFunctions = <T>(obj: T) => {
  const newObj = {} as { [K in keyof T]: T[K] extends Function ? never : K };
  
  for (const key in obj) {
    if (!(obj[key] instanceof Function)) {
      newObj[key] = obj[key];
    }
  }

  return newObj;
};

const result = ExcludeFunctions({ name: "John", age: 30, sayHello: () => console.log("Hello") });

console.log(result); // Output: { name: "John", age: 30 }

Omit functions from category

Answer №1

Similar questions

Create the correct structure for an AWS S3 bucket

Tips for fixing the TS2345 compilation error when working with React

The constructor for Observable, as well as static methods such as `of` and `from`, are currently

Tips for executing Firebase transactions involving read operations subsequent to write operations

Guide to seamlessly incorporate a HTML template into your Angular 7 project

Error TS2322: The specified type Login cannot be assigned to the given type

BS Modal was improperly invoked, leading to an illegal instantiation

Add a class to a button in an Angular btn-group if a specific string is found within an

Is it feasible to customize Angular Material Constants within select.ts?

Assembly of these elements

Tips for preventing a promise from being executed more than once within an observable while being subscribed to a BehaviorSubject

Issue detected in TypeScript code - "Could not locate property 'setSelectedFile' in type 'void'.ts(2339)"

Angular Routing can be a powerful tool for managing multiple article posts in an efficient and organized way

Got a value of `false` for an attribute `closable` that is not meant to be a

Classify the array types based on their indexes within the map

Creating a unified environment variable for Angular 2 and ASP.NET Core MVC: A comprehensive guide

When integrating external HTML into an Angular 2 component, relative references may become invalid and fail to

Is the Angular Karma test failing to update the class properties with the method?

Exploring Real-Time Typescript Validation in Next.JS

Issues with Cross-Origin Resource Sharing (CORS) have been identified on the latest versions of Android in Ionic Cordova. However, this problem does not