TypeScript enums cannot be used as a value when imports using the `import type` declaration

Question

🕗 Version Information

TypeScript v4.1.3 Node.js v10.23.1 linux/amd64

⏯ REPL Link

https://replit.com/@AnmSaiful/ts-import-type-enum

💻 Code

// ---- enums.ts ----
export enum Sex {

  Male    = "male",
  Female  = "female",

}

// ---- type.ts ----
export * as Enum from "./enums";

// ---- index.ts ----
import type { Enum } from "./type";

function enumTest(): Enum.Sex {

  return Enum.Sex.Male;

}

console.log( enumTest() );

🙁 Actual behavior

It does not allow using Enum from the composed imported type and says:

'Enum' cannot be used as a value because it was imported using 'import type'.

🙂 Expected behavior

It should allow using Enums from the imported type.

I'm using import type to avoid failing ESLint's no-cycle rule because my type imports result from circular dependency. — A.N.M. Saiful Islam
– A.N.M. Saiful Islam, Commented Jul 13, 2021 at 7:27

Lin Du · Accepted Answer · 2021-07-13 04:18:34Z

5

TS 3.8 add Type-Only Imports and Export feature.

import type only imports declarations to be used for type annotations and declarations. It always gets fully erased, so there’s no remnant of it at runtime.

Just import the enum like this:

import { Enum } from './type';

answered Jul 13, 2021 at 4:18

Lin Du

104k139 gold badges341 silver badges575 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

A.N.M. Saiful Islam Over a year ago

I'm using import type to avoid failing ESLint's no-cycle rule because my type imports result from circular dependency. It is normal because the type definition file uses the class file (for the instance type), and class file uses the type definition file.

A.N.M. Saiful Islam Over a year ago

Currently, I'm using plain objects as const along with typeof Obj[ keyof typeof Obj] as a workaround. Hopefully, TS will solve the enum issue soon.

Lin Du Over a year ago

@A.N.M.SaifulIslam A simple way to solve circular dependency: A->B, B->A, create another file C, A->C, B->C. What stops you to do this?

A.N.M. Saiful Islam Over a year ago

There are a lot of such circular dependencies (just for types) and just to get rid of this issue creating a lot of additional files for a single purpose is meaningless. I hope TS will natively support it shortly.

keikai · Accepted Answer · 2022-03-08 05:02:13Z

2

just fixed your issue in below link https://replit.com/@aMITrAI11/ts-import-type-enum#index.ts

enums.ts

export enum Sex {
  Male    = "male",
  Female  = "female",
}

type.ts

export * as Enum from "./enums";

index.ts

import { Enum } from "./type";

function enumTest() {
  return Enum.Sex.Male;
}

console.log(enumTest());

edited Mar 8, 2022 at 5:02

keikai

15.3k10 gold badges56 silver badges73 bronze badges

answered Jul 13, 2021 at 3:47

Amit Rai

4071 gold badge4 silver badges22 bronze badges

1 Comment

A.N.M. Saiful Islam Over a year ago

I'm using import type to avoid failing ESLint's no-cycle rule because my type imports result from circular dependency. It is normal because the type definition file uses the class file (for the instance type), and class file uses the type definition file.

Collectives™ on Stack Overflow

TypeScript enums cannot be used as a value when imports using the `import type` declaration

🕗 Version Information

⏯ REPL Link

💻 Code

🙁 Actual behavior

🙂 Expected behavior

2 Answers 2

4 Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

🕗 Version Information

⏯ REPL Link

💻 Code

🙁 Actual behavior

🙂 Expected behavior

2 Answers 2

4 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related