From: Jörg "F. Wittenberger" <[email protected]> Subject: Re: [Chicken-users] handling the undefined value Date: Thu, 25 Nov 2010 22:42:15 +0100
> Am Donnerstag, den 25.11.2010, 22:34 +0100 schrieb Felix: >> From: Jörg "F. Wittenberger" <[email protected]> >> Subject: Re: [Chicken-users] handling the undefined value >> Date: Thu, 25 Nov 2010 16:24:01 +0100 >> >> > Am Mittwoch, den 24.11.2010, 18:53 +0100 schrieb Felix: >> >> From: Jörg "F. Wittenberger" <[email protected]> >> >> Subject: Re: [Chicken-users] handling the undefined value >> >> Date: Mon, 22 Nov 2010 15:08:46 +0100 >> >> >> >> > Have a compiler switch (since it may break some code), which changes the >> >> > code to return zero values instead of the distinguished undefined value. >> >> >> >> I don't think this is a great idea: this will change the >> >> semantics of code using call-with-values, >> > >> > So far I did not come around to test, whether or not I'll be able to >> > find my undefined value with the new scrutinizer version. >> >> Unfortunately I had to disable this feature again. We probably need >> some sort of "style" warning switch (there are too many places where >> procedures without result or undefined result use forms like `when'). > > Sadly. > > The "style" warning I'd like to avoid if all possible. Me too. > > I'd rather vote for changing the syntax definitions (one-by-one, tell me > the git/svn/wtf reference and I'll try my best). Don't bother with it. There are quite a number of situations where a a conditional with an undefined branch must appear in tail-position. > >> > This however I don't understand. Why would it be less efficient to call >> > a continuation with zero instead of one value? >> >> There is a bit of wrapping and result-value count checking going on >> behind the scenes in that case. > > I see. I understand: could be as efficient, but that would need quite a > lot of other changes. Right? > Yes, a lot of changes. cheers, felix _______________________________________________ Chicken-users mailing list [email protected] http://lists.nongnu.org/mailman/listinfo/chicken-users
