Re: fn:foot, fn:truncate, fn:item-at

Hi Benito,

> Have we forgotten about the last() function? It can do these things rather simple and is also shorter:

True, fn:last can help. Unfortunately, it works different to
fn:head(), and other languages (such as Lisp or Haskell) have
counterparts for head and tail as well. Positional tests in predicates
and fn:last won’t help us, for example, if we chain functions or pass
on functions as items.

> Elsewhere I had proposed to allow sequences of numbers in filter expressions, then one could also write even shorter $seq[1 to last() - 1]

I also think this would have been a nice decision in earlier years. If
I remember correctly, MarkLogic supported this as proprietary

> Look at this lizard 🦎:
> First comes the head, then two feet and then the tail.

;) Somewhat true. On the other hand, if you subtract a head from a
body, it may depend on both the perspective and the species if you
want to regard the remaining leftovers as tail. I liked the fn:foot
and fn:truncate proposals, but maybe there are better names (Haskell
uses "init" instead of "truncate"… but I assume their main motivation
was the character length).


Received on Wednesday, 2 December 2020 15:05:21 UTC