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TypeScript error

TS1250

Function declarations are not allowed inside blocks in strict mode when targeting 'ES5'.

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

The error message

Function declarations are not allowed inside blocks in strict mode when targeting 'ES5'.
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 2026-09-25T01:43:12.670Z.