Typescript: Export default on interface not allowed

Created on 18 May 2015 · 5Comments · Source: microsoft/TypeScript

Raised on SO. The following is an error:

export default interface Foo {
}

By design or bug?

By Design

Source

basarat

👍8

Most helpful comment

It's by design. You can accomplish the exact same effect with

interface Foo {
    // stuff
}
export default Foo;

More discussion in #3095.

ahejlsberg on 18 May 2015

👍14

All 5 comments

It's by design. You can accomplish the exact same effect with

interface Foo {
    // stuff
}
export default Foo;

More discussion in #3095.

ahejlsberg on 18 May 2015

👍14

I'm OK with leaving it as is if the reasoning is that interfaces, et al, are not vaid EcmaScript and #3917 is implemented.

clavecoder on 3 Jul 2016

hi all,

i unexpectedly encountered this too.

@ahejlsberg, can you clarify on your remarks further? the discussion in #3095 seems to be focusing more on the declaration collisions, which is all said and good.

@clavecoder, i don't fully see the rationale you point to. Interfaces aren't valid ecmascript either, so why shed convention?

these remarks are (of course) stated in a cordial tone. however, this decision feels very counterintuitive to me

cdaringe on 22 Nov 2016

Allowing export default + [interface / abstract class / enum / namespace / type ] is tracked by https://github.com/Microsoft/TypeScript/issues/3792