This is a reference entry from TypeScript diagnosticMessages.json. A full explanation with fixes has not been written yet.
Function declarations are not allowed inside blocks in strict mode when targeting 'ES5'. Modules are automatically in strict mode.
{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 2026-09-25T01:43:12.670Z.