In my code, I have implemented the factory method pattern. However, some instances using this pattern end up with circular dependencies. Removing these dependencies has proven to be a challenge for me. To illustrate, consider the following example:
// factoryMethod.ts
import Instance1 from './Instance1';
import Instance2 from './Instance2';
import Instance3 from './Instance3';
import { Instance, InstanceName } from './Instance';
export const getInstanceByName = (
instanceName: InstanceName
): Instance => {
switch (instanceName) {
case 'Instance1':
return Instance1;
case 'Instance2':
return Instance2;
case 'Instance3':
return Instance3;
default:
throw new Error();
}
};
// extremelyHelpfulUtilityFunction.ts
import { getInstanceByName } from './factoryMethod';
export const extremelyHelpfulUtilityFunction = (instanceName: InstanceName): number => {
// An illustrative utility function
return getInstanceByName(instanceName).num
}
// Instance.ts
export interface Instance {
doSomething: () => number;
num: number;
}
export type InstanceName = 'Instance1' | 'Instance2' | 'Instance3';
// Instance1.ts
import { extremelyHelpfulUtilityFunction } from './extremelyHelpfulUtilityFunction';
const i: Instance = {
doSomething: (): number => {
return extremelyHelpfulUtilityFunction('Instance2') + extremelyHelpfulUtilityFunction('Instance3'); // circular dependency
},
}
export default i;
// Other instances defined below, you get the idea.
As I compile this code using rollup, it raises a warning about the circular dependencies present. Although the code functions correctly, I am determined to eliminate this warning. How can I refactor the code so that InstanceX can access InstanceY without creating a circular dependency?