consistentTypeDefintions, @typescript-eslint/consistent-type-definitions

[jpike88]

Often developers will write types and interfaces in interchangeable ways:

// type alias
type T1 = {
  a: string;
  b: number;
};

// interface keyword
interface T2 {
  a: string;
  b: number;
}

It's more consistent to require the above type T1 to be defined as an interface as it 'looks' like one.

https://github.com/typescript-eslint/typescript-eslint/blob/main/packages/eslint-plugin/docs/rules/consistent-type-definitions.md

[ematipico]

I would consider this proposal a very low priority. And not recommended.

Rome had a rule called useInterface but we removed because people can use whatever they want.

I would argue, instead, that it's better to create type by default, and interface when needed.

[Conaclos]

The TypeScript team advocates the use of interface over type. At the beginning of TypeScript type was poorly supported. However, it is no longer the case. The community use the two syntaxes.

I personally prefer type because it does not allow unsafe declaration merging.

I pretty like how Flow distinguishes interface and type:

• type for exact (no extra properties) literal objects
• interfaces for inexact literal objects, class's implements

Thus, in my view these two syntaxes communicate distinct intentions and programming paradigms. Both should be allowed. I think we should not implement this rule.

[jpike88]

I see your feedback and actually agree with you. My thinking is from an older time, it’s not relevant anymore. Closing