Typescript Error "Variable is of type 'undefined'."

During our work on the codebase yesterday, everything went smoothly without any issues.

However, this morning we encountered a new problem where every error is now being classified as Unknown instead of the previous any type.

Is there a way to undo this change? I've searched through numerous confusing GitHub conversations that hint at the change, but none of them specify in which version this breaking change was introduced.

Thank you in advance.

Answer №1

There are no specific details provided regarding the version in which this breaking change was introduced.

Introducing a new feature in TypeScript 4.4 where catch parameters now default to unknown, enhancing error handling safety. A workaround for the issue of

"useUnknownInCatchVariables": false
exists.

My recommendation is to refrain from altering this setting to ensure future code safety. Instead, consider adding explicit any where appropriate or implementing custom type guards to leverage existing code's safety features.

Further Resources

Answer №2

After extensive research, I stumbled upon this solution buried in a playground comment...

"useUnknownInCatchVariables": false,
setting in the compiler options should resolve the issue.

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