This is a reference entry from TypeScript diagnosticMessages.json. A full explanation with fixes has not been written yet.
The right-hand side of an 'instanceof' expression must be either of type 'any', a class, function, or other type assignable to the 'Function' interface type, or an object type with a 'Symbol.hasInstance' method.
{0}, {1} and so on are filled in by the compiler.
- Category
- Error
- Severity
- error
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Source: TypeScript diagnosticMessages.json. Data fetched 2026-09-25T01:43:12.671Z.