On 19 дек, 01:42, MonkeeSage <MonkeeS... / gmail.com> wrote: > On Dec 18, 10:23 am, DNNX <6aLLIaPu... / gmail.com> wrote: > > > On 18 , 17:54, Robert Klemme <shortcut... / googlemail.com> wrote: > > > > On one hand you are right. On the other hand, begin and end indexes > > > are asymmetric anyway: you know that the starting index is always 0 > > > but the ending index can have arbitrary values. ... > > > Hm... On the other hand, end and begin indexes are asymmetric anyway: > > you know that the ending index is always -1 but the starting index can > > have arbitrary values. > > > Isn't this a symmetry? > > > Best regards, > > Viktar > > No, because "-1" is a special value...it's got magic in it. It can > magically mean 5, or 10, or even 12 (because it's magic). ;) "-1" is > just sugar for #length, and #length is always a side-effect of a > container, whereas '0' is a constant entry point. > > Regards, > Jordan -1 is more special and magic than 0? Hm... 0 also can magically mean -6, -11, or even -13 (because it's magic too). -1 is sugar for #length? Not sure I understand correctly. Never heard such an interpretation of -1 earlier. Why #length but not #length-1? Why 0 is not sugar for -#length? What do you mean saying -1 is a sugar for something? 0 is a constant entry point? Great, -1 is a constant exit point. Anyway, is there any symmetry or no, I still believe that returning 'asd' in one case and nil in other is not consistent (please see my example in the first message). Regards, Viktar