Error handling expectations

I'm working on adding a tuple_data_record function to pageinspect to
parallel tuple_data_split (returning the record type of the relation being
examined rather than an array of attributes as on-disk byte data).

This my first real foray into the Postgres codebase, so an beginner
question: I noticed that existing C functions in pageinspect often do error
checking and then report the error with ereport but still continue on to
execute the rest of the function instead of early returning. Is this
standard practice? Or should I be reporting the error and then cleaning up
and returning rather than continuing to execute?

Thanks,
James Coleman