Given how easy chained relational ops make explicit range checking with endpoints, e.g.
$a <= $x <= $b Imd be perfectly happy with a Range smartmatching only the elements that you get out of the RangeIterator. On 8/27/09, smuj <s...@iol.ie> wrote: > TSa wrote: >> HaloO, >> >> David Green wrote: >>> For certain discrete ordered types, like Int, both ways work out the >>> same, and since Ints are the most common and most obvious use for >>> Ranges, it's easy to overlook the confusion. The case with strings is >>> a good example: it really doesn't make sense that a value not produced >>> by a range nevertheless lies between its endpoints. Why not have a >>> separate Interval type? >> >> I see no problem when a Range matches for values which are not produced >> by a RangeIterator. I expect 2.5 ~~ 1..5 to be true even though 2.5 is >> not in 1,2,3,4,5. > > I suspect that the double meaning of Ranges is going to confuse some > people and bite others. If things stay as they are, I hope that the use > of :by will be flagged as a syntax error if used in literal Range smart > matching. Of course, that doesn't help the unsuspecting when variables > are being used, ala 2.5 ~~ $myrange. > > (For the record, 2.5 ~~ '!'..5 is also true on my system, although I > don't know why! I certainly wouldn't expect it though :) > >> The same applies for 'aaa' ~~ 'aa'..'az'. I find this >> quite natural. > > Not sure if you're saying that's something you'd like or if you think > that that's something already there. It doesn't match for me using > recent(ish) Rakudo. Of course, that could just be me! :) > > I'd personally prefer it if Ranges just did lists, including when smart > matching, but had an interval method or such like for explicit matching > against the endpoints, e.g. > > 2.5 ~~ interval(1..5) # or > 2.5 ~~ $myrange.interval > > I'm new in town though, so I'll happily admit that I don't know the full > implications of such a change. Having context-insensitive Ranges DWIM's > better to me, but DWIMery, like beauty, is clearly in the eye of the > beholder! :) > > Cheers, > -- > smuj > -- Sent from my mobile device Mark J. Reed <markjr...@gmail.com>
