[erlang-questions] Any wisdom to offer on "tagged return values"
mats cronqvist
masse@REDACTED
Sat May 2 23:50:36 CEST 2009
"Kevin" <q2h46uw02@REDACTED> writes:
> In the "programming rules"
> http://www.erlang.se/doc/programming_rules.shtml#REF32551
>
>
> ---snip--------------------------------------
> Use tagged return values.
My $0.02 is that this advice is, and always has been, hogwash. It is
a rare function that can return several valid answers. So, the
default should be to return a valid answer, i.e. one that can be
used directly, or throw an error.
My theory is that the people who wrote this "programming rule" were
(good) C programmers, and thus felt a need to check if the value
returned was ok before they dared use it.
>
>
> Ironically in the lists man page it says keysearch is deprecated in
> favor of keyfind, which does exactly what the programming rules
> cautions against.
>
> keyfind(Key, N, TupleList) -> Tuple | false
Indeed.
mats
More information about the erlang-questions
mailing list