I've been out of the loop for a while. So are we done for 2001, or is there more we can accomplish in the remaining days of this year? And what should we put...
It appears that the functions that return "like Current" can be implemented in at least two different ways: 1) clone (Current) 2) create Result.make_empty /...
... Yes, because it _is_ like Current. ... But this would not be like Current ... or I am missing something. As a function Result, it seems to me that like...
Dominique Colnet
dominique.colnet@...
Dec 19, 2001 8:52 pm
2545
... Why? The fact that it is "like Current" does not intrinsically mean that their attributes should have the same values. ... Why? "like Current" is a type,...
... [...] ... That was also my understanding. Every property the result must have except the type needs to be specified in the postcondition. "like Current"...
... Yes. The question is whether the descendant can rely on the default implementation (the values of the attributes) or it should redefine all the functions...
... I think I still don't understand what you mean. Do you mean that there are some implicit postconditions that are not inherited? Or dou you mean that in a...
... No. ... No. ... Yes, this is my concern. For example, class COLOR_STRING inherit STRING creation make, make_empty, make_filled feature color: ... -- The...
... [...] ... [nice example with colored string snipped] O.K., I see your point. I think in cases where the class invariant (executable or not) has changed,...
... The class invariant is preserved by either clone or make/make_empty. So the result does not violate the class invariant. I think, creating the result that...
... The result of clkone, make /make_empty does not. But the result of a "like Current" function might. Thjis can happen if the class invariant of the child is...
... Let's look at the code class COLOR feature color_rgb: ... f: like Current is do -- Obtain the new object Result := clone (Current) -- Class invariant is...
... You do not miss my point. I think I missed yours for some time. I hope I have it now. In a clean design the problem I describe only happens in procedures, ...
Sorry to come into this thread quite late. ... When we worked on "making STRING safe in descendants", we based our specifications on the following assumption: ...
... In passing, I started to try to rewrite the UC_STRING class from Gobo by making it inherit from STRING. I guess that I am the first one to try to write a...
Arno Wagner wrote: ... Yes, either thing can be wrong, but I would prefer to have one (possibly wrong) thing in all ELKS-compatible implementations rather than...
... I agree that we want an efficient 'substring', but I don't think we need to make any tradeoff between convenience and efficiency. Provided STRING.substring...
The Gobo UC_STRING class provides a library-based way to handle Unicode characters. This is a great vendor-independent way to support Unicode, though it's not...
... YES! A simple solution would be sufficient IMO. UC_STRING in Gobo can handle the full details, complete support + discussion via NICE will take years. So...
... Which is different from what you said earlier: variant 2 suggested by Alexander explicitly states that `clone' _should_ be called. ... I for one would...
... How do we specify the encoding? (I guess, the compiler should understand the encoding used in the source file automatically.) Regards, Alexander Kogtenkov ...
... I can understand that. The advantage would be that people know they need to pay attention. Regards, Arno -- Arno Wagner Dipl. Inform. ETH Zuerich...
... Good point. For UTF16 we can do (byte order mark) that, but AFAIK we cannot distinguish between UTF8 and ISO-8859-1. Perhaps for UTF8 we need a compiler...
... Yes and no. I don't think it should be part of the ELKS classes as Unicode support is much more than having simply Unicode support. One has to take care of...
... Well, a while ago I thought about it and one possible solution was to consider special kind of index clause with "encoding" tag. E.g. indexing encoding:...
Hello, As I wrote in a message yesterday, I'm currently rewriting Gobo's UC_STRING by making it inherit from STRING and providing it with the STRING ELKS 2001...
... The advantage of having Unicode supported by Eiffel compilers rather than just by a third-party library is that compilers can provide a way to have...
