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Description
🔎 Search Terms
export void
export reserved
export null
🕗 Version & Regression Information
- Reproducible since typescript v4. In older releases, it doesn't export anything. I also tried the latest dev release (5.9.0-dev.20250716)
- This is the behavior in every version I tried, and I reviewed the FAQ for entries about
exports
⏯ Playground Link
Playground (important: lang:javascript)
💻 Code
Using the following tsconfig.json
:
{
"compilerOptions": {
"target": "esnext",
"lib": ["esnext"],
"module": "esnext",
"allowJs": true,
"checkJs": true,
"declaration": true,
"declarationMap": true,
"outDir": "./dist",
"emitDeclarationOnly": true,
"strict": true,
"noImplicitAny": true,
"moduleResolution": "bundler"
}
}
I compile declaration files for this code ${project}/schema.js
(only happens when compiling javascript):
const _null = {}
const $void = {}
export { _null as null, $void as void }
🙁 Actual behavior
The produced declaration file schema.d.ts
is erroneous. It has duplicate identifiers:
declare const _null: {};
declare const $void: {};
export { _null as null, _null as null, $void as void, _void as void };
🙂 Expected behavior
No duplicate identifiers:
declare const _null: {};
declare const $void: {};
export { _null as null, $void as void };
Additional information about the issue
For any reserved keyword, tsc
always exports _{reserved} as {reserved}
, whenever {reserved}
is exported. Even though the variable _{reserved}
does not exist.
It is only reproducible when compiling javascript.