El jue., 4 oct. 2018 a las 4:53, Trey Harris (<t...@lopsa.org>) escribió:
> > On Wed, Oct 3, 2018 at 22:21 ToddAndMargo <toddandma...@zoho.com> wrote: > >> >> On 04/10/2018 03:07, ToddAndMargo wrote: >> >>> Hi All, >> >>> >> >>> In another thread, Timo wrote me: >> >>> >> >>> The "-->" part of the signature is optional. If there isn't >> >>> one, it defaults to Mu, which is the type that everything >> >>> conforms to, i.e. the sub or method that either has "--> Mu" >> >>> explicitly, or has it by leaving it out, may return >> >>> absolutely whatever it wants. >> >>> >> >>> After all, the "-->" part is a constraint, and it gets >> >>> validated at compile time every time a sub or method >> >>> returns. >> >>> >> >>> I got to thinking, some routines do not return anything. Without >> >>> the "-->" constraint, how am I to determine if something is >> >>> being returned? >> >>> >> >>> Yours in confusion, >> >>> -T >> >> On 10/3/18 6:44 PM, Timo Paulssen wrote: >> > I just spotted a grave mistake in my earlier mail: >> > >> > the --> constraints are validated at *run* time, not *compile* time; >> > that's a very big difference, and an important one. Of course "every >> > time a sub or method returns" doesn't make much sense if i had meant >> > "compile time", but I felt i should really point it out before causing >> > too much confusion. >> > >> >> Hi Timo, >> >> Thank you for the help over on the chat line with IN! >> >> My confusion is not that it returns something (Mu). >> >> My confusion is "what" it returns. > > > I'm not clear on what you mean. When "--> XXX" is given, then an XXX is > returned. When no "-->" is given, it technically returns Mu but you can > pretend it is like a Pascal/Module "procedure" that does not return > anything. > Or anything that is a subclass of Mu. That is, anything. JJ
