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Data Types · easy

9. Response Types (ok, err)

Standardized success and rollback error types.

1 min read2 questionsup to 50 XPtopic 9/50

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A `response` represents `(ok val)` or `(err val)`. Returning an `err` from a public function automatically aborts and rolls back all state mutations.

clarity
(ok true)
(err u404)

How to study this topic

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  1. 1. What happens when a public function returns (err ...)?

  2. 2. What must public functions return?

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