- From: Dimitre Novatchev <dnovatchev@yahoo.com>
- Date: Sat, 22 Nov 2003 07:23:20 -0800 (PST)
- To: public-qt-comments@w3.org
Allowing the functions fn:max, fn:min and fn:avg to accept an empty sequence as argument is wrong and will make using these functions difficult and confusing. Trying to calculate the minimum, maximum or average of an empty sequence is an error and must be reported at the place where this error occurs. Returning the empty sequence instead is delaying the moment at which it is realized that there is an error. This will lead to hidden, long-time undiscovered errors and to difficulty in tracking the exact cause of an error, as there has not been an immediate raising of an error as reaction to the exact cause. Why should the programmer be forced to manually include additional code to check the type of the returned value and manually raise an error, if this can be done automatically by the type-checking system? Note: These comments apply to all cases in the WD, which allow an empty sequence argument, for which the function has no meaning. In all such cases the type of the function must be changed to accept a non-empty sequence. It is necessary to analyze all cases where a fn:function is returning the empty sequence and to decide case by case whether having such a result is meaningful. It is a benefit of typing that such errors can be caught (even sometimes statically) and immediately reported in all cases. Dimitre Novatchev __________________________________ Do you Yahoo!? Free Pop-Up Blocker - Get it now http://companion.yahoo.com/
Received on Saturday, 22 November 2003 10:23:32 UTC