Free practice · boolean · easy
Practice
Validate before conversion
When numeric input arrives as text, code should define allowed text forms and handle failed conversion rather than assuming every value is valid.
Trusted input boundary
Business logic receives only validated, typed values
- PresenceRequired value supplied
- FormatAllowed external form
- ConvertFocused typed conversion
- RangeAllowed business limits
- UsePass checked value to logic
- ReportReturn useful safe failures
Presence, type, format, conversion, and range checks belong at a narrow boundary with useful failures and no hidden fallback.