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TS: Using an exported class declaration locally in a type annotation

See original GitHub issue

The following snippet…

export class Foo<T = any> {};
let foo: Foo = new Foo();
let foo: Foo<any> = new Foo();

…compiles to…

"use strict";Object.defineProperty(exports, "__esModule", {value: true}); class Foo {} exports.Foo = Foo;;
let foo = exports.Foo = new Foo();
let foo = new Foo();

Notice how exports.Foo is being re-assigned. 😳

sucrase v3.9.4
node v11.3.0

Issue Analytics

State:
Created 5 years ago
Comments:5 (5 by maintainers)

Top GitHub Comments

1reaction

alangpiercecommented, Jan 11, 2019

Yikes, thanks for the report. Here’s a slightly simpler test case:

export class Foo {}
let foo: Foo = new Foo();

Playground link

0reactions

aleclarsoncommented, Jan 11, 2019

Nope, I say go for it. 🎉

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