Microsoft/TypeScript
View on GitHubUnexpected "used before its declaration" error when implementing a exported type of a merged namespace
Open
#54,429 opened on May 28, 2023
BugDomain: BinderHelp Wanted
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Description
Bug Report
🔎 Search Terms
used before its declaration vscode
🕗 Version & Regression Information
- tested in 4.7.3, 5.0.4 and nightly
⏯ Playground Link
Playground link with relevant code
💻 Code
namespace Foo {
export interface Bar { }
}
class X implements Foo.Bar {
}
const Foo = 1;
🙁 Actual behavior
In VSCode it reports:
namespace Foo
Block-scoped variable 'Foo' used before its declaration.ts(2448)
Untitled-1(9, 7): 'Foo' is declared here.
Variable 'Foo' is used before being assigned.ts(2454)
You may not see the error immediately if you paste the code into a new file. It will appear when you start typing something.
Note that the error cannot be reproduced in the playground.
🙂 Expected behavior
No error.