How do I split a TypeScript class into multiple files?

by

Lately I use this pattern:

// file class.ts
import { getValue, setValue } from "./methods";

class BigClass {
    public getValue = getValue;
    public setValue = setValue;

    protected value = "a-value";
}

// file methods.ts
import { BigClass } from "./class";

function getValue(this: BigClass) {
    return this.value;
}

function setValue(this: BigClass, value: string ) {
   this.value = value;
}

This way we can put methods in a seperate file. Now there is some circular dependency thing going on here. The file class.ts imports from methods.ts and methods.ts imports from class.ts. This may seem scary, but this is not a problem. As long as the code execution is not circular everything is fine and in this case the methods.ts file is not executing any code from the class.ts file. NP!

You could also use it with a generic class like this:

class BigClass<T> {
    public getValue = getValue;
    public setValue = setValue;

    protected value?: T;
}

function getValue<T>(this: BigClass<T>) {
    return this.value;
}

function setValue<T>(this: BigClass<T>, value: T) {
    this.value = value;
}

More Related Contents:

  1. difference between variables in typescript
  2. Function that takes an input between 0 and 5 and outputs an array of 5 elements that will be used for generating 5 stars in the UI [closed]
  3. How do I return the response from an Observable/http/async call in angular?
  4. Can’t perform a React state update on an unmounted component
  5. Property ‘…’ has no initializer and is not definitely assigned in the constructor
  6. Calling webpacked code from outside (HTML script tag)
  7. Limited parallelism with async/await in Typescript/ES7
  8. Angular 4.3.3 HttpClient : How get value from the header of a response?
  9. How to reduce javascript object to only contain properties from interface
  10. In Angular, how do you determine the active route?
  11. Throttle amount of promises open at a given time
  12. ‘package.json’ is not under ‘rootDir’
  13. Typescript – Extending Error class
  14. What’s the difference between “declare class” and “interface” in TypeScript
  15. VueJS/Typescript – Cannot find module ‘./components/Navigation’ or its corresponding type declarations
  16. Error: ‘types’ can only be used in a .ts file – Visual Studio Code using @ts-check
  17. Call a function on click event in Angular 2
  18. How to make TypeScript output valid ES6 module import statements?
  19. Visual Studio Code Syntax Highlighting not working for Javascript and Typescript [closed]
  20. How to Pass data from child to parent component Angular
  21. Angular2 too many file requests on load
  22. Should we use useCallback in every function handler in React Functional Components
  23. Server Discovery And Monitoring engine is deprecated
  24. TypeScript, Looping through a dictionary
  25. How to return a promise when writestream finishes?
  26. Filter Array in Array by date between 2 dates
  27. What’s the purpose of a leading pipe when declaring a type on Typescript
  28. How to apply both ValidationPipe() and ParseIntPipe() to params?
  29. import * as React from ‘react’; vs import React from ‘react’;
  30. How to import a js library without definition file in typescript file

Leave a Comment