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TypeScript error

TS1055

Type '{0}' is not a valid async function return type in ES5 because it does not refer to a Promise-compatible constructor value.

Reference entryTypeScriptFetched
This is a reference entry from TypeScript diagnosticMessages.json. A full explanation with fixes has not been written yet.

The error message

Type '{0}' is not a valid async function return type in ES5 because it does not refer to a Promise-compatible constructor value.
As listed by TypeScript diagnosticMessages.json

{0}, {1} and so on are filled in by the compiler.

Details

Category
Error
Severity
error

Related errors

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Source: TypeScript diagnosticMessages.json. Data fetched 2026-09-25T01:43:12.668Z.