Avoid circular dependencies in Angular 6 to ensure proper association between modules

When working with TypeScript, how should I handle the scenario where

  • Cat has an owner: Person
  • Person owns a pet: Cat

Cat

import {Person} from './person'
export class Cat {

    owner: Person

    constructor(){
        this.owner = new Person()
    }

}

Person

import {Cat} from './cat'
export class Person {

    pet: Cat

    constructor(){
        this.pet = new Cat()
    }

}

I am hoping for a solution or pattern that does not involve:

  • putting both classes in the same file
  • introducing a third class

Please don't tell me that the TypeScript compiler overlooked this case :$

Answer №1

After identifying my mistake, I realized that I was creating an instance of Cat within the Person class and an instance of Person within the Cat class.

To prevent this redundancy that arises from a loop of creating instances like

cat => Person => Cat => Person...
,

I decided to move the creation of both Cat and Person instances
  • into separate methods
  • or simply passing them to the constructor can solve the issue as well

    constructor(anOwner: Person) { this.owner = anOwner }

Check out this stackblitz example for reference.

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