On Tue, Oct 5, 2010 at 1:31 PM, Wolfgang Rohdewald <wolfg...@rohdewald.de> wrote: > On Dienstag 05 Oktober 2010, MRAB wrote: >> > About notation, even if loved right-hand-half-open >> > intervals, I would wonder about [a,b] noting it. I guess >> > 99.9% of programmers and novices (even purely amateur) have >> > learnt about intervals at school in math courses. Both >> > notations I know of use [a,b] for closed intervals, while >> > half-open ones are noted either [a,b[ or [a,b). Thus, for >> > me, the present C/python/etc notation is at best >> > misleading. So, what about a hypothetical language using >> > directly math unambiguous notation, thus also letting >> > programmers chose their preferred semantics (without >> > fooling others)? End of war? >> >> Dijkstra came to his conclusion after seeing the results of >> students using the programming language Mesa, which does >> support all 4 forms of interval. > > what was his conclusion?
That right-hand-half-open intervals (i.e. a <= i < b, equivalently [a, b) ), which are what Python uses, are to be preferred. (See aforelinked PDF: http://www.cs.utexas.edu/users/EWD/ewd08xx/EWD831.PDF) Cheers, Chris -- http://mail.python.org/mailman/listinfo/python-list
