typescript class and namescript hierarchy when do importing

Question

I have a question about name conflict but didn't cause any errors and seems to export pre usual to the outside scope. Best way to show is in this simplify code;

Endpoints.model.ts

namespace Endpoints {
 export class FruitWorld {
  apple: string;
  banana: string;
  seller: string;
  sellerId: string;
  get produceDate() {
   ...
  }
 }
}
export class FruitWorld extended Endpoints.FruitWorld {
 Seller: string;
 SellerId: string;
 get ProduceDate() {
  ...
 }
 constructor(...init: Partial<Endpoints.FruitWorld>[]) {
  super();
  init.map(data => {
   delete data.Apple;
   delete data.Banana;
   Object.assign(this, data);
  }
 }
}
export namespace FruitWorld {
 // Some overwrite function 
 // extended functionalities
}

app.ts

import { FruitWorld } "./Endpoints.model";

Here is the confusing part, which one of the FruitWorld is being imported here? From what I can tell, it is the class get imported.

I read this stackover question and this stackover question, but they are not really touching on what if we have a class and a namespace share same name, and exists in the same file. Which gets export?

Hmm, good question, best way to find out would be to try different attributes names in each FruitWorld class and see the one which is defined I guess ? — Sebastien Servouze
– Sebastien Servouze, Commented May 16, 2018 at 11:55
Hi @SebastienServouze I think the class inside the namespace Endpoints is not a problem here, because it is encapsulated by the namespace and it can only be used in the local file. My concern is the namespace and class share same name. — roger
– roger, Commented May 16, 2018 at 12:05

Estus Flask · Accepted Answer · 2018-05-16 12:17:15Z

4

Class export will be overridden by a namespace if a namespace is non-empty:

export class Foo { }

export namespace Foo {
    let bar;
}

So it persists in compiler output:

var Foo = /** @class */ (function () {
    function Foo() {
    }
    return Foo;
}());
exports.Foo = Foo;
(function (Foo) {
    var bar;
})(Foo = exports.Foo || (exports.Foo = {}));
exports.Foo = Foo;

And class export won't be overridden by a namespace if it's empty:

export class Foo { }

export namespace Foo {
    // let bar;
}

So it's removed from compiler output:

var Foo = /** @class */ (function () {
    function Foo() {
    }
    return Foo;
}());
exports.Foo = Foo;

edited May 16, 2018 at 12:17

answered May 16, 2018 at 12:12

Estus Flask

226k79 gold badges478 silver badges620 bronze badges

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

Collectives™ on Stack Overflow

typescript class and namescript hierarchy when do importing

1 Answer 1

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related