You are avoiding the questions. If they deal with Nil NULL etc. fine then it should be easy to answer the questions.
However, if you don't answer the questions then that's fine. ----- Original Message ----- From: "Alan K. Stebbens" <[email protected]> Date: Saturday, September 5, 2009 11:44 Subject: Re: [Jchat] wishlist adverb: ignore indices To: Chat forum <[email protected]> > Many other computer languages deal with non-data just fine, some > old, > some new: > > SQL 92: NULL > Ruby: nil > Python: None > Objective C: nil > > The nice thing about Ruby's OO methodology is that if you want > to > extend a particular operator onto nil, you can: > > class String ; def empty?(v); v.length == 0; > end; end > class Array; def empty?(v); > v.size == 0; end; end > class Hash; def empty?(v); > v.size == 0; end; end > class NilClass; def empty?(v); > true; end; end > > # test whether obj is empty or nil > if obj.empty? > ... > > > > On Sep 5, 2009, at 11:27 AM, Roger Hui wrote: > > > NO DATA, like NaN, should be treated with caution. > > For example, what are the answers to the following > > questions? > > > > NODATA = NODATA > > NODATA = 314159 > > NODATA ~: NODATA > > NODATA > NODATA > > $ NODATA > > 3 $ NODATA > > NODATA $ 3 > > 3+NODATA > > 0 1 2,NODATA > > /: 0 1 2,NODATA > > < NODATA > >> NODATA > > NODATA e. a. > > > > Last but not least, > > > > NODATA=NaN > > > > > > > > ----- Original Message ----- > > From: James C Field <[email protected]> > > Date: Saturday, September 5, 2009 11:13 > > Subject: Re: [Jchat] wishlist adverb: ignore indices > > To: Chat forum <[email protected]> > > > >> Raul Miller wrote: > >>> On Thu, Sep 3, 2009 at 4:22 PM, James C > >> Field<[email protected]> wrote: > >>> > >>>> What do you want the "fill" marker to be? > >>>> Blank fill for character or zero fill for integer? Real or > >> imaginary?>> Perhaps a simple extension such as used in APL TAKE. > >>>> > >>> > >>> I do not understand how your question relates to what I > >>> want: What is a "marker"? > >>> > >>> But, yes, fill would be 0 for numbers, space for characters > >>> and ace for boxes. > >>> > >>> > >> A MARKER in my conception is an indication in or of a data field > >> that no > >> data is present or offered. Data is simply absent. Programmers > >> frequently employ subterfuges or special flags or tags to > >> indicate that > >> there is no data in a field. Theis practice could be > >> characterised as a > >> kludge. > >> > >> NO DATA should be a universally understood condition in data > >> storage and > >> retrieval. APL take used zero and blank as fill. > >> > >> I propose that NO DATA should be a useful alternative fill. > >> Obviously > >> this is complicated in its implications but, I think, worth > thought. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
